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Synonyms

ac

1 American  

abbreviation

  1. acre; acres.


Ac 2 American  

abbreviation

Chemistry.
  1. acetate.

  2. acetyl.


Ac 3 American  
Symbol, Chemistry.
  1. actinium.


AC 4 American  

abbreviation

Electricity.
  1. alternating current.


A/C 5 American  
[ey-see] / ˈeɪˈsi /
Also AC, or a/c

abbreviation

  1. air conditioning.


A/C 6 American  
Or a/c

abbreviation

Bookkeeping.
  1. account.

  2. account current.


ac- 7 American  
  1. variant of ad- before c and qu: accede; acquire.


-ac 8 American  
  1. variant of -ic after Greek noun stems ending in i: cardiac; maniac.


a.c. 9 American  

abbreviation

  1. (in prescriptions) before meals.


A.C. 10 American  

abbreviation

  1. before Christ.


A.C. 11 American  

abbreviation

  1. Army Corps.

  2. Athletic Club.


a.c. 1 British  

abbreviation

  1. (in prescriptions) ante cibum

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

AC 2 British  

abbreviation

  1. alternating current Compare DC

  2. ante Christum

  3. Air Corps

  4. athletic club

  5. Companion of the Order of Australia

  6. appellation d'origine contrôlée: the highest French wine classification; indicates that the wine meets strict requirements concerning area of production, strength, etc See VDQS vin de pays vin de table

  7. Aelodau'r Cynulliad: Member of the Assembly (that is, the National Assembly of Wales)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

ac 3 British  

abbreviation

  1. Ascension Island

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

A/C 4 British  

abbreviation

  1. Air Commodore

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

a/c 5 British  

abbreviation

  1. account

  2. account current

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Ac 6 British  

symbol

  1. actinium

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

AC Scientific  
  1. Abbreviation of alternating current


Etymology

Origin of -ac8

From Latin -acus, from Greek -akos

Origin of a.c.9

From Latin ante cibum

Origin of A.C.10

From Latin ante Christum

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Our Welsh language friends can start listening to the big match build-up now by using the Carl ac Alun link above.

From BBC Mar. 25, 2024

He was a very well-known, established character ac even before "I Love Lucy."

From Fox News Jun. 5, 2021

The Multiplication Property of Equality—For any numbers a, b, and c, if a = b , then ac = bc .

From Textbooks Apr. 22, 2020

Comparing not having A/C to 100 years ago when there was no ac is not a fair comparison.

From New York Times Aug. 15, 2016

It stood just ac ross from the cobhoust, a tumbledown shed full of stuff left there in Grandpa Dowdel’s time.

From "A Long Way from Chicago" by Richard Peck

An agent from Homeland Security Investigations determined that Balcarcel Ac has had two previous deportations, the affidavit states.

From Seattle Times Jul. 11, 2022

Both men are being held in local jails, Balcarcel Ac in Charlottesville and Alvarado-Dubon in Richmond.

From Seattle Times Jul. 8, 2022

Even to copy a relatively short paper, “Proc Nat Ac Sci”—“Proceedings of the National Academy of Sciences”—could take the better part of an hour.

From The New Yorker Jan. 6, 2020

Actinium, Ac, is the first member of the fourth transition series, which also includes Rf through Rg.

From Textbooks Feb. 14, 2019

Ac forst ich wolle wite;     for ȝoure mochele worsipe. f.

From Selections from early Middle English, 1130-1250 Part I: Texts by Hall, Joseph

Delac, now 33, currently plays for AC Horsens in Denmark.

From BBC Jul. 25, 2026

"We're looking at 35C-plus heat in houses that were not designed for it, with people who are not as able to regulate their temperature, and can't necessarily afford to just fit an AC," Windram said.

From BBC Jul. 24, 2026

But, beyond the concerns about the future of the business and the daunting costs of the AC unit, Griffin emphasized the importance of community during a challenging time.

From Los Angeles Times Jul. 22, 2026

The pet hospital lost one of two AC units, meaning the facility is able to keep animals in its care and their human clients comfortable.

From Los Angeles Times Jul. 22, 2026

I leaned my forehead against the cool glass, reaching over to point the AC vent directly at my face.

From "The Darkest Minds" by Alexandra Bracken

Appeared in the July 25, 2026, print edition as 'Notable & Quotable: A/C'.

From The Wall Street Journal Jul. 24, 2026

Older APOE2 knock-in mice had smaller nucleoli, higher levels of the nuclear scaffolding protein Lamin A/C, and better-preserved heterochromatin in the hippocampus than mice carrying APOE3 or APOE4.

From Science Daily Jul. 24, 2026

Ferrari reveals its new EV, the UN shares an alternative metric to GDP, and Europe won’t embrace A/C despite deadly heatwaves.

From Slate May 30, 2026

And the maximum possible efficiency of SMACool is still lower than that of conventional air conditioning, although the aim is to beat the energy efficiency of A/C.

From BBC May 19, 2025

Roy waited inside for a while, but without A/C it was unbearably hot and sticky.

From "Hoot" by Carl Hiaasen

Still, with the prices of many commodities climbing, the companies couldn’t ac- commodate price shocks, so they often  wound  up hiring banks to hedge their vulnerability to volatile product markets.

From MSNBC Jun. 4, 2014

“I suppose the problem at the moment is that we don’t have a one- to-one mapping, because even our best theories aren’t completely ac- curate,” Ladyman said.

From Scientific American Jan. 31, 2014

The government has devised civic ac- tion programs to rebuild damaged hamlets, and anti-guerrilla patrols are often accompanied by doctors who bring free medical care to the hill people.

From Time Magazine Archive

Very democratic, proud of being a plain American, she likes people, is always ac- cessible to strangers.

From Time Magazine Archive

And when the drummers, ac- cepting his drink, raised their glasses and said, “Here’s to you,” Charles was delighted.

From "East of Eden" by John Steinbeck

NOTE.—The suffix -ac is found only in Latin derivatives of Greek origin.

From New Word-Analysis by William Swinton

A new report finds that about 3% of autos--high- and low-end models--have fungi and bacteria breeding in the moisture that collects on the a.c.

From Time Magazine Archive

It turned out that all electricity here was d.c., conjured up by commanding the electrons in a wire to move in one direction, and completely useless with a.c. motors.

From The Sky Is Falling by Del Rey, Lester

Power.—A transformer for stepping down a commercial alternating current for lighting and heating the filament and for stepping up the commercial a.c., for charging the plate of a vacuum tube oscillator.

From The Radio Amateur's Hand Book by Collins, A. Frederick (Archie Frederick)

The 60 h.p. has parallel a.c. cylinders, the other two are radial w.c.

From Jane's All the World's Aircraft 1913 by Various

These writings are said to date from about 97 to 150 a.c.

From Frauds and Follies of the Fathers A Review of the Worth of their Testimony to the Four Gospels by Wheeler, Joseph Mazzini

Other historical Pasadena figures in the book include the bookseller A.C.

From The Wall Street Journal Feb. 27, 2026

Tired of having to scrap their way through the streets of West Compton in the early 1970s, A.C.

From Los Angeles Times Feb. 22, 2025

But the filmmaking team is fairly confident it belongs to Irvine, due to the sock found inside the boot being embroidered with the words "A.C. Irvine".

From BBC Oct. 11, 2024

Other students, not so much — they were stuck in older dorms without A.C.

From New York Times Jun. 19, 2024

On October 11th the detrainment of the 2nd A.C. was completed and Sir Horace moved his two divisions into position between Aire and Béthune.

From The First Seven Divisions Being a Detailed Account of the Fighting from Mons to Ypres by Hamilton, Ernest W.

Chris Coucheron-Aamot, a guest at the Sandals resort, wrote on Facebook that the cause of the episode “may have been a fault with the a/c in the unit, causing a toxic coolant leak.”

From Seattle Times May 9, 2022

During this meeting, Spencer noted some 30 claims which he attributes to Bashir, including Jephson's alleged plots against her: "Jephson - dangerous: money. Left offshore a/c in March 1994".

From BBC May 20, 2021

If that power comes from fossil fuels, a/c alone will account for a half-degree Celsius rise in global temperatures.

From The Guardian Aug. 11, 2019

Not a single prison should get a/c before all the schools in our nation have a/c.

From New York Times Aug. 20, 2016

Curry wrote asking what price I placed on my right to the books, and I replied demanding a full a/c of all sales up to date.

From Charles Lever, His Life in His Letters, Vol. I by Downey, Edmund

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