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Variant of ad-..
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

AC or A.C.

1. air conditioning.
2. Also, ac, a.c., alternating current.
3. before Christ.
[< Latin ante Christum]


1. acetate.
2. acetyl.


Chem. Symbol.


var. of ad- before c and qu: accede; acquire.


var. of -ic after Greek noun stems ending in i: cardiac; maniac.
[< Latin -acus < Greek -akos]


or a/c,

1. account.
2. account current.
3. air conditioning.


(in prescriptions) before meals.
[< Latin ante cibum]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in classic literature ?
He said he had cursed his soul to rags; and yet he would not get down from his horse, neither would he take any rest, or listen to any comfort, until he should have found Sir Ossaise and settled this ac- count.
He was one of those who could torture the slightest look, word, or gesture, on the part of the slave, into impudence, and would treat it ac- cordingly.
There is so much going on that they do not have time to grow old," she told herself with a grim little smile, and went resolutely about the business of becoming ac- quainted with people.