To be prone to something means you have a natural tendency toward it or are likely to experience it. If you're prone to colds, you catch them more often than most people. If your little brother is prone to accidents, he's always tripping, bumping into things, or spilling his juice.

The word often appears with negative things: someone might be prone to worry, prone to losing their temper, or prone to making careless mistakes when rushing. But it can describe neutral tendencies too. A scientist might be prone to asking questions, or a creative student might be prone to daydreaming.

Prone also describes a physical position: lying face down, flat on your stomach. Swimmers practice the prone float, floating face down in the water. Soldiers might crawl in a prone position to stay hidden.

The opposite of prone is supine, lying face up on your back, though that's a word you'll encounter less often. When doctors or coaches talk about body positions, they'll specify prone versus supine so everyone knows exactly which way someone should be facing.