To stir means to mix something by moving it around in circles with a spoon, stick, or other tool. When you stir hot chocolate, you're moving the spoon through the liquid to blend the chocolate powder with the milk. Cooks stir soup to keep it from burning on the bottom of the pot, and bakers stir cake batter to combine flour, eggs, and sugar into a smooth mixture.

The word also describes causing movement or activity. A breeze might stir the leaves on a tree, making them rustle and shift. When a story stirs your imagination, it gets your mind moving and thinking about new ideas. If a speech stirs a crowd, it excites people and moves them to action.

You might also hear someone say “don't stir up trouble,” meaning don't cause problems or get people upset about something. When someone stirs from sleep, they're beginning to wake up and move around.

As a noun, a stir can mean a small movement or sign of activity, like the first stir of someone waking up. A person who creates excitement or gets things moving can be called a stirring personality, and a powerful speech might be described as stirring because it moves people emotionally.