Au Look up Au at Dictionary.com
chemical symbol for "gold," from Latin aurum "gold" (see aureate).
au Look up au at Dictionary.com
French, "at the, to the," from Old French al, contraction of a le, with -l- softened to -u-, as also poudre from pulverem, chaud from calidus, etc. Used in many expressions in cookery, etc., which have crossed the Channel since 18c., such as au contraire, literally "on the contrary;" au gratin, literally "with scrapings;" au jus, literally "with the juice."