au

¹ American  

[oh] / oʊ /

French.

plural

aux

1. to the; at the; with the.

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Au ² American  

abbreviation

1. author. Also au

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Au ³ American  

Symbol, Chemistry.

1. gold.

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AU ⁴ American  

abbreviation

1. astronomical unit.

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A.U. ⁵ American  

Or a.u.

abbreviation

1. angstrom unit.

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Au ¹ British  

symbol

1. gold

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au ² British  

abbreviation

1. Australia

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AU ³ British  

abbreviation

1. African Union

2. Also: a.u..  angstrom unit

3. Also: a.u..  astronomical unit

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AU Scientific  

1. Abbreviation of astronomical unit

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Etymology

Origin of Au

From the Latin word aurum

Example Sentences

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

I snagged a pain au chocolat for the flight.

From The Wall Street Journal • Mar. 18, 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

Towers of onion rings stacked high, bone-in rib-eyes, bubbling pots of lobster mac and cheese, fries and meats drowning in au poivre.

From Los Angeles Times • Oct. 31, 2025

I also told him that my father had confirmed that any au pair that was placed by them must be a nonsmoker or be willing to stop smoking.

From "Silent To The Bone" by E.L. Konigsburg