Vinegar is an acid liquid produced from the fermentation of ethanol in a process that yields its key ingredient, acetic acid (ethanoic acid). It also may come in a diluted form. The acetic acid concentration typically ranges from 4% to 8% by volume for table vinegar and up to 18% for pickling. Natural vinegars also contain small amounts of tartaric acid, citric acid, and other acids. Vinegar has been used since ancient times and is an important element in European, Asian, and other cuisines.

The word "vinegar" derives from the Old French vin aigre, meaning "sour wine", which in turn is derived from the Latin "vinum aegrum" meaning "feeble wine".

Balsamic vinegar, red and white wine vinegar

Vinegar is commonly infused with spices or herbs—as here, with oregano