Achilles’ heel

to be aching all over

acid

acid head

acid test

to do acid

to be acquainted with Henry Miller

to acquiesce in an arrangement

I acquiesced in it.

I acquire a language.

to acquire a taste for it

to acquire a fortune

to acquire a habit

to acquire money in the short term

It’s an acquired taste

across-the-board

to go across something

across the pond

Act your age [and not your shoe size]

to act the artist

to act the innocent

to act in the spirit of someone

to act on behalf of another person

to act as a model to a painter

act of negligence