[A]

Achillean adj. Invulnerable.
achromatic adj. Colorless,
acid n. A sour substance.
acidify v. To change into acid.
acknowledge v. To recognize; to admit the genuineness or validity of.
acknowledgment n. Recognition.
acme n. The highest point, or summit.
acoustic adj. Pertaining to the act or sense of hearing.
acquaint v. To make familiar or conversant.
acquiesce v. To comply; submit.
acquiescence n. Passive consent.
acquire v. To get as one's own.
acquisition n. Anything gained, or made one's own, usually by effort or labor.
acquit v. To free or clear, as from accusation.
acquittal n. A discharge from accusation by judicial action.
acquittance n. Release or discharge from indebtedness, obligation, or responsibility.
acreage n. Quantity or extent of land, especially of cultivated land.
acrid adj. Harshly pungent or bitter.
acrimonious adj. Full of bitterness.
acrimony n. Sharpness or bitterness of speech or temper.
actionable adj. Affording cause for instituting an action, as trespass, slanderous words.
actuality n. Any reality.
actuary n. An officer, as of an insurance company, who calculates and states the risks and premiums.
actuate v. To move or incite to action.
acumen n. Quickness of intellectual insight, or discernment; keenness of discrimination.
acute adj. Having fine and penetrating discernment.
adamant n. Any substance of exceeding hardness or impenetrability.
addendum n. Something added, or to be added.
addle v. To make inefficient or worthless; muddle.
adduce v. To bring forward or name for consideration.
adhere v. To stick fast or together.
adherence n. Attachment.
adherent adj. Clinging or sticking fast.
adhesion n. The state of being attached or joined.
adieu inter. Good-by; farewell.
adjacency n. The state of being adjacent.
adjacent n. That which is near or bordering upon.
adjudge v. To award or bestow by formal decision.
adjunct n. Something joined to or connected with another thing, but holding a subordinate place.
adjuration n. A vehement appeal.
adjutant adj. Auxiliary.
administrator n. One who manages affairs of any kind.
admissible adj. Having the right or privilege of entry.
admittance n. Entrance, or the right or permission to enter.
admonish v. To warn of a fault.
admonition n. Gentle reproof.
ado n. unnecessary activity or ceremony.
adoration n. Profound devotion.
adroit adj. Having skill in the use of the bodily or mental powers.
adulterant n. An adulterating substance.
adulterate v. To make impure by the admixture of other or baser ingredients.
adumbrate v. To represent beforehand in outline or by emblem.
advent n. The coming or arrival, as of any important change, event, state, or personage.
adverse adj. Opposing or opposed.
adversity n. Misfortune.
advert v. To refer incidentally.
advertiser n. One who advertises, especially in newspapers.
advisory adj. Not mandatory.
advocacy n. The act of pleading a cause.
advocate n. One who pleads the cause of another, as in a legal or ecclesiastical court.
aerial adj. Of, pertaining to, or like the air.
aeronaut n. One who navigates the air, a balloonist.
aeronautics n. the art or practice of flying aircraft
aerostat n. A balloon or other apparatus floating in or sustained by the air.
aerostatics n. The branch of pneumatics that treats of the equilibrium, pressure, and mechanical properties.
affable adj. Easy to approach.
affect v. To act upon
affectation n. A studied or ostentatious pretense or attempt.
affiliate n. Some auxiliary person or thing.
affirmative adj. Answering yes; to a question at issue.
affix v. To fasten.
affluence n. A profuse or abundant supply of riches.
affront n. An open insult or indignity.
afire adv. & adj. On fire, literally or figuratively.
afoot adv. In progress.
aforesaid adj. Said in a preceding part or before.
afresh adv. Once more, after rest or interval.
afterthought n. A thought that comes later than its appropriate or expected time.
agglomerate v. To pile or heap together.
aggrandize v. To cause to appear greatly.
aggravate v. To make heavier, worse, or more burdensome.
aggravation n. The fact of being made heavier or more heinous, as a crime, offense, misfortune, etc.
aggregate n. The entire number, sum, mass, or quantity of something.
aggress v. To make the first attack.
aggression n. An unprovoked attack.
aggrieve v. To give grief or sorrow to.
aghast adj. Struck with terror and amazement.
agile adj. Able to move or act quickly, physically, or mentally.
agitate v. To move or excite (the feelings or thoughts).
agrarian adj. Pertaining to land, especially agricultural land.
aide-de-camp n. An officer who receives and transmits the orders of the general.
ailment n. Slight sickness.
airy adj. Delicate, ethereal.
akin adj. Of similar nature or qualities.
alabaster n. A white or delicately tinted fine-grained gypsum.