Vinegary describes something that tastes, smells, or feels like vinegar: sharp, sour, and a bit biting. When pickles sit in their jar too long, they can become overly vinegary. A salad dressing might have a pleasantly vinegary tang, or it might be so vinegary it makes you pucker.

The word also describes a person's mood or manner when they're being sharp and sour in their words or attitude. A vinegary response is tart and critical, like when someone answers a simple question with an irritated “Obviously” or rolls their eyes while explaining something. A teacher having a bad day might give vinegary replies to students' questions, speaking in clipped, impatient tones.

Think of how actual vinegar feels on your tongue: it has a bite to it, a sharpness that makes you react. That's exactly how vinegary behavior feels. Someone in a vinegary mood is sour and prickly, responding to others with an edge that stings a little. The word captures both the acidic quality of the liquid and the acidic quality of an unpleasant attitude.