A civilian is someone who is not a member of the military or police force. In other words, most people you know are civilians: your teachers, neighbors, mail carrier, and dentist are all civilians because they don't serve in the armed forces or law enforcement.

The distinction becomes especially important during wartime. International laws protect civilians from being targeted in combat because they're not soldiers and aren't fighting. A civilian can support their country in wartime by working in factories, hospitals, or farms, but they aren't part of the military chain of command.

The word can also describe things that relate to ordinary life rather than military life. Civilian clothes are regular everyday outfits, as opposed to military uniforms. When soldiers finish their service and return to civilian life, they're resuming normal routines like going to college or starting a business.

Sometimes people use “civilian” playfully to describe someone outside a particular specialized group. A doctor might jokingly call non-medical people “civilians,” or a musician might use the term for people who don't play instruments. But the primary meaning always refers to people who aren't in the military or law enforcement.