militia

noun

1. 1. Archaic any military force
   2. later, any army composed of citizens rather than professional soldiers, called up in time of emergency
2. ☆ in the U.S., all able-bodied male citizens between 18 and 45 years old who are not already members of the regular armed forces: members of the National Guard and of the Reserves (of the Army, Air Force, Coast Guard, Navy, and Marine Corps) constitute the ; all others, the
3. any of various disaffected groups of citizens that are organized as to resemble an army and that oppose the authority of the federal government