Chill is a relaxed, calm, or laid-back quality. When someone describes a person as chill, they mean that person doesn't get worked up easily, stays relaxed in stressful situations, and is easy to be around. A chill teacher might not panic when the projector stops working during a presentation. A chill friend doesn't freak out when plans change at the last minute.

The word can also be a verb meaning to relax or calm down. After a busy day at school, you might want to chill by reading or playing a game. If someone's getting unnecessarily upset about a small problem, a friend might say “just chill” to suggest they relax.

As a noun, a chill is a feeling of coldness, like the chill in the air on an autumn morning or the chill you feel when you're coming down with a fever. Something chilly is moderately cold, not freezing but cool enough to need a sweater.

When something sends a chill down your spine, it means it frightens you or makes you uneasy. Reading a suspenseful story might give you chills.