Stir

Stir is a word with multiple related senses, used as both a verb and a noun. As a verb, to stir means to mix or move a substance, especially a liquid, by making gentle circular or other motions with a spoon, stick, or other implement. Stirring helps distribute heat, incorporate ingredients, or prevent separation. It can also mean to provoke or cause to begin to move or operate, as in to stir interest or to stir the crowd. In informal contexts, to stir up means to incite or provoke.

As a noun, a stir refers to the act of stirring—the movement involved or the result of being stirred. In cooking and laboratories, it describes the process and the motion. The phrase a stir can also denote a disturbance or commotion in a place or among people, as in there was a small stir about the announcement. In British slang, the stir is prison or jail; doing time in the stir is an informal expression. The adjective stir-crazy describes boredom or mental unrest caused by confinement.

Stirring is influenced by viscosity, heat, and equipment. In cooking, stirring prevents scorching and promotes a uniform texture. In laboratories and industrial settings, mechanical or magnetic stirrers are used to mix liquids, often with a stir bar or impeller. The concept is fundamental to fluid dynamics, contributing to convective mixing and diffusion.