militia If you live in a remote place that's under attack by an upstart band of thieves, start a militia. A militia is a band of civilians trained to do army type business, without officially joining the army. Militia comes from mīlet-, Latin for soldier, but the word now refers to a band of fighters who aren't officially soldiers. Sometimes militias add on to regular army forces, like the citizen's militias who fought alongside regular troops in the Revolutionary War.