To stimulate means to cause something to become more active, to grow, or to develop. When a teacher asks thought-provoking questions in class, she stimulates discussion and gets students thinking. When scientists study how the brain works, they discover that reading stimulates areas involved in imagination and language.

The word often appears when something encourages growth or activity. Exercise stimulates your muscles to become stronger. A good book can stimulate your curiosity about a subject. Parents might give children puzzles and games that stimulate their minds. Cities create programs to stimulate economic growth by encouraging new businesses to open.

Stimulation is the noun form. Babies need stimulation from their environment (sounds, colors, textures) to help their brains develop. Students need intellectual stimulation to stay engaged and learn. Too little stimulation leads to boredom, but too much can become overwhelming.

The opposite is suppress or inhibit, which means to hold back or reduce activity. While coffee stimulates your nervous system and makes you feel alert, certain medications suppress your appetite and make you less hungry.