Definition of vinegar

• a. - A sour liquid used as a condiment, or as a preservative, and obtained by the spontaneous (acetous) fermentation, or by the artificial oxidation, of wine, cider, beer, or the like.
• a. - Hence, anything sour; -- used also metaphorically.
• v. t. - To convert into vinegar; to make like vinegar; to render sour or sharp.