astute
(adj.) very clever, crafty
asylum
atone
(v.) to repent, make amends
atrophy
(v.) to wither away, decay
attain
(v.) to achieve, arrive at
attribute
atypical
(adj.) not typical, unusual
audacious
(adj.) excessively bold
audible
(adj.) able to be heard
augment
(v.) to add to, expand
auspicious
(adj.) favorable, indicative of good things
austere
(adj.) very bare, bleak
avarice
(n.) excessive greed
avenge
(v.) to seek revenge
aversion
(n.) a particular dislike for something
buffet
burnish
(v.) to polish, shine
buttress
coup
(n.) a brilliant, unexpected act
covet
(v.) to desire enviously
covert
(adj.) secretly engaged in
credulity
(n.) readiness to believe
crescendo
(n.) a steady increase in intensity or volume
criteria
(n.) standards by which something is judged