A moderate but penetrating coldness. A sensation of coldness, often accompanied by shivering and pallor of the skin. A checking or dampening of enthusiasm, spirit, or joy: bad news that put a chill on the celebration. A sudden numbing fear or dread. Moderately cold; chilly: a chill wind. Not warm and friendly; distant: a chill greeting. Discouraging; dispiriting: "Chill penury repressed their noble rage\u201d ( Thomas Gray). To affect with or as if with cold. To lower in temperature; cool. To make discouraged; dispirit. Metallurgy To harden (a metallic surface) by rapid cooling. To be seized with cold. To become cold or set: jelly that chills quickly. Metallurgy To become hard by rapid cooling. Slang To calm down or relax. Often used with out. Slang To pass time idly; loiter. Often used with out. Slang To keep company; see socially. Often used with out.