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au

1 American  
[oh] / oʊ /
French.

plural

aux
  1. to the; at the; with the.


Au 2 American  

abbreviation

  1. author. Also au


Au 3 American  
Symbol, Chemistry.
  1. gold.


AU 4 American  

abbreviation

  1. astronomical unit.


A.U. 5 American  
Or a.u.

abbreviation

  1. angstrom unit.


Au 1 British  

symbol

  1. gold

"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

AU 2 British  

abbreviation

  1. African Union

  2. Also: a.u..  angstrom unit

  3. 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

au 3 British  

abbreviation

  1. Australia

"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

AU Scientific  
  1. Abbreviation of astronomical unit


Etymology

Origin of Au

From the Latin word aurum

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.

Alnour Mohamed Ali, a Sudanese national, was charged with endangering life after the four people died while trying to board a water taxi off the coast of Saint Etienne au Mont, near Calais.

From BBC • Apr. 11, 2026

On the menu is uni pasta, hanger steak au poivre and a dry-aged burger with fries, which restaurant critic Bill Addison says doesn’t require any twists because “it’s simply a fantastic burger.”

From Los Angeles Times • Mar. 9, 2026

But with some notable exceptions—Henri-Georges Clouzot’s “Diabolique,” Julien Duvivier’s “Panique” and Jacques Becker’s “Touchez pas au Grisbi” among them—much of this tradition remains unknown to American viewers.

From The Wall Street Journal • Jan. 21, 2026

It’s exactly what it sounds like: toasted French or Italian bread soaked in the rich, savory au jus of an Italian beef sandwich.

From Salon • Dec. 7, 2025

She complained there was no “cafe au lait”-colored construction paper for her skin, or “sixty-percent-cacao-chocolate” color for her eyes.

From "When You Reach Me" by Rebecca Stead