daring – Brave.
darkling – Blindly.
Darwinism – The doctrine that natural selection has been the prime cause of evolution of higher forms.
dastard – A base coward.
datum – A premise, starting-point, or given fact.
dauntless – Fearless.
day-man – A day-laborer.
dead-heat – A race in which two or more competitors come out even, and there is no winner.
dearth – Scarcity, as of something customary, essential ,or desirable.
death’s-head – A human skull as a symbol of death.
debase – To lower in character or virtue.
debatable – Subject to contention or dispute.
debonair – Having gentle or courteous bearing or manner.
debut – A first appearance in society or on the stage.
decagon – A figure with ten sides and ten angles.
decagram – A weight of 10 grams.
decaliter – A liquid and dry measure of 10 liters.
decalogue – The ten commandments.
Decameron – A volume consisting of ten parts or books.
decameter – A length of ten meters.
decamp – To leave suddenly or unexpectedly.
decapitate – To behead.
decapod – Ten-footed or ten-armed.
decasyllable – A line of ten syllables.
deceit – Falsehood.
deceitful – Fraudulent.
deceive – To mislead by or as by falsehood.
decency – Moral fitness.
decent – Characterized by propriety of conduct, speech, manners, or dress.
deciduous – Falling off at maturity as petals after flowering, fruit when ripe, etc.
decimal – Founded on the number 10.
decimate – To destroy a measurable or large proportion of.
decipher – To find out the true words or meaning of, as something hardly legible.
decisive ad. Conclusive.
declamation – A speech recited or intended for recitation from memory in public.
declamatory – A full and formal style of utterance.
declarative – Containing a formal, positive, or explicit statement or affirmation.
declension – The change of endings in nouns and – to express their different relations of gender.
decorate – To embellish.
decorous – Suitable for the occasion or circumstances.
decoy – Anything that allures, or is intended to allures into danger or temptation.
decrepit – Enfeebled, as by old age or some chronic infirmity.
dedication – The voluntary consecration or relinquishment of something to an end or cause.
deduce – To derive or draw as a conclusion by reasoning from given premises or principles.
deface – To mar or disfigure the face or external surface of.
defalcate – To cut off or take away, as a part of something.
defamation – Malicious and groundless injury done to the reputation or good name of another.
defame – To slander.
default – The neglect or omission of a legal requirement.
defendant – A person against whom a suit is brought.
defensible – Capable of being maintained or justified.
defensive – Carried on in resistance to aggression.
defer – To delay or put off to some other time.
deference – Respectful submission or yielding, as to another’s opinion, wishes, or judgment.
defiant – Characterized by bold or insolent opposition.
deficiency – Lack or insufficiency.
deficient – Not having an adequate or proper supply or amount.
definite – Having an exact signification or positive meaning.
deflect – To cause to turn aside or downward.
deforest – To clear of forests.
deform – To disfigure.
deformity – A disfigurement.
defraud – To deprive of something dishonestly.
defray – To make payment for.
degeneracy – A becoming worse.
degenerate – To become worse or inferior.
degradation – Diminution, as of strength or magnitude.
degrade – To take away honors or position from.
dehydrate – To deprive of water.
deify – To regard or worship as a god.
deign – To deem worthy of notice or account.
deist – One who believes in God, but denies supernatural revelation.
deity – A god, goddess, or divine person.
deject – To dishearten.
dejection – Melancholy.
delectable – Delightful to the taste or to the senses.
delectation – Delight.
deleterious – Hurtful, morally or physically.
delicacy – That which is agreeable to a fine taste.
delineate – To represent by sketch or diagram.
deliquesce – To dissolve gradually and become liquid by absorption of moisture from the air.
delirious – Raving.
delude – To mislead the mind or judgment of.
deluge – To overwhelm with a flood of water.
delusion – Mistaken conviction, especially when more or less enduring.
demagnetize – To deprive (a magnet) of magnetism.
demagogue – An unprincipled politician.
demeanor – Deportment.
demented – Insane.
demerit – A mark for failure or bad conduct.
demise – Death.
demobilize – To disband, as troops.
demolish – To annihilate.
demonstrable – Capable of positive proof.
demonstrate – To prove indubitably.
demonstrative – Inclined to strong exhibition or expression of feeling or thoughts.
demonstrator – One who proves in a convincing and conclusive manner.
demulcent – Any application soothing to an irritable surface
demurrage – the detention of a vessel beyond the specified time of sailing.
dendroid – Like a tree.
dendrology – The natural history of trees.
denizen – Inhabitant.
denominate – To give a name or epithet to.
denomination – A body of Christians united by a common faith and form of worship and discipline.
denominator – Part of a fraction which expresses the number of equal parts into which the unit is divided.
denote – To designate by word or mark.
denouement – That part of a play or story in which the mystery is cleared up.
denounce – To point out or publicly accuse as deserving of punishment, censure, or odium.
dentifrice – Any preparation used for cleaning the teeth.
denude – To strip the covering from.
denunciation – The act of declaring an action or person worthy of reprobation or punishment.
deplete – To reduce or lessen, as by use, exhaustion, or waste.
deplorable – Contemptible.
deplore – To regard with grief or sorrow.
deponent – Laying down.
depopulate – To remove the inhabitants from.
deport – To take or send away forcibly, as to a penal colony.
deportment – Demeanor.
deposition – Testimony legally taken on interrogatories and reduced to writing, for use as evidence in court.
depositor – One who makes a deposit, or has an amount deposited.
depository – A place where anything is kept in safety.
deprave – To render bad, especially morally bad.
deprecate – To express disapproval or regret for, with hope for the opposite.
depreciate – To lessen the worth of.
depreciation – A lowering in value or an underrating in worth.
depress – To press down.
depression – A falling of the spirits.
depth – Deepness.
derelict – Neglectful of obligation.
deride – To ridicule.
derisible – Open to ridicule.
derision – Ridicule.
derivation – That process by which a word is traced from its original root or primitive form and meaning.
derivative – Coming or acquired from some origin.
derive – To deduce, as from a premise.
dermatology – The branch of medical science which relates to the skin and its diseases.
derrick – An apparatus for hoisting and swinging great weights.
descendant – One who is descended lineally from another, as a child, grandchild, etc.
descendent – Proceeding downward.
descent – The act of moving or going downward.
descry – To discern.
desert – To abandon without regard to the welfare of the abandoned
desiccant – Any remedy which, when applied externally, dries up or absorbs moisture, as that of wounds.
designate – To select or appoint, as by authority.
desist – To cease from action.
desistance – Cessation.
despair – Utter hopelessness and despondency.
desperado – One without regard for law or life.
desperate – Resorted to in a last extremity, or as if prompted by utter despair.
despicable – Contemptible.
despite prep. In spite of.
despond – To lose spirit, courage, or hope.
despondent – Disheartened.
despot – An absolute and irresponsible monarch.
despotism – Any severe and strict rule in which the judgment of the governed has little or no part.
destitute – Poverty-stricken.
desultory – Not connected with what precedes.
deter – To frighten away.
deteriorate – To grow worse.
determinate – Definitely limited or fixed.
determination – The act of deciding.
deterrent – Hindering from action through fear.
detest – To dislike or hate with intensity.
detract – To take away in such manner as to lessen value or estimation.
detriment – Something that causes damage, depreciation, or loss.
detrude – To push down forcibly.
deviate – To take a different course.
devilry – Malicious mischief.
deviltry – Wanton and malicious mischief.
devious – Out of the common or regular track.
devise – To invent.
devout – Religious.
dexterity – Readiness, precision, efficiency, and ease in any physical activity or in any mechanical work.
diabolic – Characteristic of the devil.
diacritical – Marking a difference.
diagnose – To distinguish, as a disease, by its characteristic phenomena.
diagnosis – Determination of the distinctive nature of a disease.
dialect – Forms of speech collectively that are peculiar to the people of a particular district.
dialectician – A logician.
dialogue – A formal conversation in which two or more take part.
diaphanous – Transparent.
diatomic – Containing only two atoms.
diatribe – A bitter or malicious criticism.
dictum – A positive utterance.
didactic – Pertaining to teaching.
difference – Dissimilarity in any respect.
differentia – Any essential characteristic of a species by reason of which it differs from other species.
differential – Distinctive.
differentiate – To acquire a distinct and separate character.
diffidence – Self-distrust.
diffident – Affected or possessed with self-distrust.
diffusible – Spreading rapidly through the system and acting quickly.
diffusion – Dispersion.
dignitary – One who holds high rank.
digraph – A union of two characters representing a single sound.
digress – To turn aside from the main subject and for a time dwell on some incidental matter.
dilapidated pa. Fallen into decay or partial ruin.
dilate – To enlarge in all directions.
dilatory – Tending to cause delay.
dilemma – A situation in which a choice between opposing modes of conduct is necessary.
dilettante – A superficial amateur.
diligence – Careful and persevering effort to accomplish what is undertaken.
dilute – To make more fluid or less concentrated by admixture with something.
diminution – Reduction.
dimly – Obscurely.
diphthong – The sound produced by combining two vowels in to a single syllable or running together the sounds.
diplomacy – Tact, shrewdness, or skill in conducting any kind of negotiations or in social matters.
diplomat – A representative of one sovereign state at the capital or court of another.
diplomatic – Characterized by special tact in negotiations.
diplomatist – One remarkable for tact and shrewd management.
disagree – To be opposite in opinion.
disallow – To withhold permission or sanction.
disappear – To cease to exist, either actually or for the time being.
disappoint – To fail to fulfill the expectation, hope, wish, or desire of.
disapprove – To regard with blame.
disarm – To deprive of weapons.
disarrange – To throw out of order.
disavow – To disclaim responsibility for.
disavowal – Denial.
disbeliever – One who refuses to believe.
disburden – To disencumber.
disburse – To pay out or expend, as money from a fund.
discard – To reject.
discernible – Perceivable.
disciple – One who believes the teaching of another, or who adopts and follows some doctrine.
disciplinary – Having the nature of systematic training or subjection to authority.
discipline – To train to obedience.
disclaim – To disavow any claim to, connection with, or responsibility to.
discolor – To stain.
discomfit – To put to confusion.
discomfort – The state of being positively uncomfortable.
disconnect – To undo or dissolve the connection or association of.
disconsolate – Grief-stricken.
discontinuance – Interruption or intermission.
discord – Absence of harmoniousness.
discountenance – To look upon with disfavor.
discover – To get first sight or knowledge of, as something previously unknown or unperceived.
discredit – To injure the reputation of.
discreet – Judicious.
discrepant – Opposite.
discriminate – To draw a distinction.
discursive – Passing from one subject to another.
discussion – Debate.
disenfranchise – To deprive of any right privilege or power
disengage – To become detached.
disfavor – Disregard.
disfigure – To impair or injure the beauty, symmetry, or appearance of.
dishabille – Undress or negligent attire.
dishonest – Untrustworthy.
disillusion – To disenchant.
disinfect – To remove or destroy the poison of infectious or contagious diseases.
disinfectant – A substance used to destroy the germs of infectious diseases.
disinherit – To deprive of an inheritance.
disinterested – Impartial.
disjunctive – Helping or serving to disconnect or separate.
dislocate – To put out of proper place or order.
dismissal – Displacement by authority from an office or an employment.
dismount – To throw down, push off, or otherwise remove from a horse or the like.
disobedience – Neglect or refusal to comply with an authoritative injunction.
disobedient – Neglecting or refusing to obey.
disown – To refuse to acknowledge as one’s own or as connected with oneself.
disparage – To regard or speak of slightingly.
disparity – Inequality.
dispel – To drive away by or as by scattering in different directions.
dispensation – That which is bestowed on or appointed to one from a higher power.
displace – To put out of the proper or accustomed place.
dispossess – To deprive of actual occupancy, especially of real estate.
disputation – Verbal controversy.
disqualify – To debar.
disquiet – To deprive of peace or tranquility.
disregard – To take no notice of.
disreputable – Dishonorable or disgraceful.
disrepute – A bad name or character.
disrobe – To unclothe.
disrupt – To burst or break asunder.
dissatisfy – To displease.
dissect – To cut apart or to pieces.
dissection – The act or operation of cutting in pieces, specifically of a plant or an animal.
dissemble – To hide by pretending something different.
disseminate – To sow or scatter abroad, as seed is sown.
dissension – Angry or violent difference of opinion.
dissent – Disagreement.
dissentient – One who disagrees.
dissentious – Contentious.
dissertation – Thesis.
disservice – An ill turn.
dissever – To divide.
dissimilar – Different.
dissipate – To disperse or disappear.
dissipation – The state of being dispersed or scattered.
dissolute – Lewd.
dissolution – A breaking up of a union of persons.
dissolve – To liquefy or soften, as by heat or moisture.
dissonance – Discord.
dissonant – Harsh or disagreeable in sound.
dissuade – To change the purpose or alter the plans of by persuasion, counsel, or pleading.
dissuasion – The act of changing the purpose of or altering the plans of through persuasion, or pleading.
disyllable – A word of two syllables.
distemper – A disease or malady.
distend – To stretch out or expand in every direction.
distensible – Capable of being stretched out or expanded in every direction.
distention – Expansion.
distill – To extract or produce by vaporization and condensation.
distillation – Separation of the more volatile parts of a substance from those less volatile.
distiller – One occupied in the business of distilling alcoholic liquors.
distinction – A note or designation of honor, officially recognizing superiority or success in studies.
distort – To twist into an unnatural or irregular form.
distrain – To subject a person to distress.
distrainor – One who subjects a person to distress.
distraught – Bewildered.
distrust – Lack of confidence in the power, wisdom, or good intent of any person.
disunion – Separation of relations or interests.
diurnal – Daily.
divagation – Digression.
divergent – Tending in different directions.
diverse – Capable of various forms.
diversion – Pastime.
diversity – Dissimilitude.
divert – To turn from the accustomed course or a line of action already established.
divertible – Able to be turned from the accustomed course or a line of action already established.
divest – To strip, specifically of clothes, ornaments, or accouterments or disinvestment.
divination – The pretended forecast of future events or discovery of what is lost or hidden.
divinity – The quality or character of being godlike.
divisible – Capable of being separated into parts.
divisor – That by which a number or quantity is divided.
divulge – To tell or make known, as something previously private or secret.
divulgence – A divulging.
docile – Easy to manage.
docket – The registry of judgments of a court.
doe – The female of the deer.
dogma – A statement of religious faith or duty formulated by a body claiming authority.
dogmatic – Making statements without argument or evidence.
dogmatize – To make positive assertions without supporting them by argument or evidence.
doleful – Melancholy.
dolesome – Melancholy.
dolor – Lamentation.
dolorous – Expressing or causing sorrow or pain.
domain – A sphere or field of action or interest.
domesticity – Life in or fondness for one’s home and family.
domicile – The place where one lives.
dominance – Ascendancy.
dominant – Conspicuously prominent.
dominate – To influence controllingly.
domination – Control by the exercise of power or constituted authority.
domineer – To rule with insolence or unnecessary annoyance.
donate – To bestow as a gift, especially for a worthy cause.
donator – One who makes a donation or present.
donee – A person to whom a donation is made.
donor – One who makes a donation or present.
dormant – Being in a state of or resembling sleep.
doublet – One of a pair of like things.
doubly – In twofold degree or extent.
dowry – The property which a wife brings to her husband in marriage.
drachma – A modern and an ancient Greek coin.
dragnet – A net to be drawn along the bottom of the water.
dragoon – In the British army, a cavalryman.
drainage – The means of draining collectively, as a system of conduits, trenches, pipes, etc.
dramatist – One who writes plays.
dramatize – To relate or represent in a dramatic or theatrical manner.
drastic – Acting vigorously.
drought – Dry weather, especially when so long continued as to cause vegetation to wither.
drowsy – Heavy with sleepiness.
drudgery – Hard and constant work in any menial or dull occupation.
dubious – Doubtful.
duckling – A young duck.
ductile – Capable of being drawn out, as into wire or a thread.
duet – A composition for two voices or instruments.
dun – To make a demand or repeated demands on for payment.
duplex – Having two parts.
duplicity – Double-dealing.
durance – Confinement.
duration – The period of time during which anything lasts.
duteous – Showing submission to natural superiors.
dutiable – Subject to a duty, especially a customs duty.
dutiful – Obedient.
dwindle – To diminish or become less.
dyne – The force which, applied to a mass of one gram for 1 second, would give it a velocity of 1 cm/s.