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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  
[ay-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:

He told her to "put 120£ in this ac… please thank u baby".

From BBC ● Jul. 13, 2026

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

From Fox News ● Jun. 5, 2021

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

Because ac = Δv / Δt , the acceleration is also toward the center; ac is called centripetal acceleration.

From Textbooks ● Aug. 12, 2015

Ngawang Doka replied in clear, sparkling English that carried a hint of a Canadian ac cent.

From "Into Thin Air" by Jon Krakauer

Balcarcel’s attorney, Samuel Simpson V, said Monday that he would be “very surprised” if Balcarcel Ac and Alvarado-Dubon were planning a mass shooting.

From Seattle Times ● Jul. 11, 2022

Balcarcel Ac was not arrested until July 5.

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 drihte ne demeð noman after his biginninge 120 Ac al his lif sal ben teald after his endinge. | ȝef þ̵ his uuel al hit is uuel ⁊ God ȝefe god his ende.

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

The researchers traced much of this problem to a phenomenon called the AC Stark shift.

From Science Daily ● Oct. 26, 2026

But surely the midweek win against AC Milan, which extended their perfect Europa League start, is enough to keep the pressure off him for now?

From BBC ● Oct. 25, 2026

AC Milan's Kaka was the last recipient before Messi and Ronaldo's tug-of-war began, the Brazilian pipping the young pair to the prize in 2007.

From BBC ● Oct. 23, 2026

But Angelenos’ ire has been especially directed at electricity bills as the extra AC needed during triple-digit heat waves landed people in the utility’s higher-cost tiers, which also have been rising.

From Los Angeles Times ● Oct. 17, 2026

But Westinghouse, whose AC system was inherently cheaper and more efficient, bid $399,000.

From "The Devil in the White City" by Erik Larson

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

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

From The Wall Street Journal ● Jul. 24, 2026

The first statement shows a payment was sent to a Barclays account where Reinaldo Avila da Silva is named as "A/C", typically an abbreviation for account.

From BBC ● Feb. 2, 2026

“Twenty-five classrooms without A/C on just Day One of 100-plus-degree weather,” one teacher told the board.

From Los Angeles Times ● Nov. 27, 2023

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

In the third century a.c. he composed in Greek a history of his native land, which has perished.

From Myths of Babylonia and Assyria by Donald Alexander Mackenzie

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 Joseph Mazzini Wheeler

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 Lester Del Rey

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

From The Wall Street Journal ● Feb. 27, 2026

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

For Caroline D’Amore, the hook was set when Bloom said he could connect her to A.C.

From Los Angeles Times ● Aug. 28, 2023

The case originally required John R. Wooden Middle School in Martinsville to allow a seventh-grader identified only as A.C. to have access to the restroom while litigation continues.

From Seattle Times ● Aug. 2, 2023

The bulk of the fighting had so far fallen on the 2nd A.C., whose casualties already amounted to 350 officers and 9,200 men.

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

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

People with no a/c had access to open windows and the wind.

From New York Times ● Aug. 15, 2016

Sales have been slow here on a/c weather is very hot.

From Potash & Perlmutter Their Copartnership Ventures and Adventures by Montague Glass

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