au

[ oh ]

/ oʊ /

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plural aux

[oh]. /oʊ/. French.

to the; at the; with the.

QUIZ

THINGAMABOB OR THINGUMMY: CAN YOU DISTINGUISH BETWEEN THE US AND UK TERMS IN THIS QUIZ?

Do you know the difference between everyday US and UK terminology? Test yourself with this quiz on words that differ across the Atlantic.

Question 1 of 7

In the UK, COTTON CANDY is more commonly known as…

candystring

candyfloss

candypuff

TAKE THE QUIZ TO FIND OUT

Compare à la.

Other definitions for au (2 of 5)

Au¹

abbreviation

author.Also au

Other definitions for au (3 of 5)

Au²

Symbol, Chemistry.

gold.

Origin of Au

From the Latin word aurum

Other definitions for au (4 of 5)

abbreviation

astronomical unit.

Other definitions for au (5 of 5)

A.U.

or a.u.

abbreviation

angstrom unit.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use au in a sentence

Well, then, b-e-c-a-u-s-e——When you find a good argument, put it into that blank.
The Atlantic Monthly, Volume 14, No. 86, December, 1864|Various
The earliest success is with the repetition of the vowels "a-u-o," but this is irregular and inaccurate.
The Mind of the Child, Part II|W. Preyer
(ii) The A-u-tsï Mostly felt-makers, who rightly or wrongly claim relationship with the Chinese.
Across China on Foot|Edwin Dingle
He spelled the word out—A-u-s-t-i-n, repeated over and over again.
The Revolt of the Star Men|Raymond Gallun

"A-u-d-r-i-e," he answered, and I trusted that Dick was too far behind to hear what we were saying.
Set in Silver|Charles Norris Williamson and Alice Muriel Williamson

British Dictionary definitions for au (1 of 3)

the internet domain name for

Australia

British Dictionary definitions for au (2 of 3)

the chemical symbol for

gold

Word Origin for Au

from New Latin aurum

British Dictionary definitions for au (3 of 3)

abbreviation for

African Union

Also: a.u. angstrom unit

Also: a.u. astronomical unit

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

Scientific definitions for au (1 of 2)

The symbol for gold.

Scientific definitions for au (2 of 2)

Abbreviation of astronomical unit