'cause - adjoining
- a war of nerves
- a wee bit
- a whole lot
- a word in season
- a-
- A-bomb
- a-going
- a-kimbo
- a-plenty
- a-smoke
- a.
- a. s. bomb
- A.C.L.S. American Council of Learned Societies
- A.D. anno Domini
- a.d.s. autograph document signed
- A.E.U. Amalgamated Engineering Union
- A.G.M. annual general meeting
- a.i. ad interim
- a.l.
- a.m.
- a.n.wt. actual net weight
- a.o. account of
- A.P.N. Atlantic Pact Nations
- A.S.P. American Society of Parasitologists
- A.T.
- A.U. astronomical unit
- a.w. atomic weight
- a/c account
- a/n above-named
- A/P Account Payable
- A/R Account Receivable
- A/T American Terms
- AA
- AAA
- AAAL American Academy of Arts and Letters
- AAAS American Association for the Advancement of Science
- AACS Airways and Air Communications Service
- AAII American Association of Individual Investors
- AAMSI American Association for Medical Systems Informatics
- AAP Affirmative Action Program