militia
n. countablen. a group of ordinary people who are trained as soldiers but are not part of the regular army. They usually only fight during an emergency.
n. a military force composed of ordinary citizens rather than professional soldiers, typically serving to supplement a regular army during an emergency.
The local militia gathered to protect the town.
Without a standing army to defend the border, the government relied on a volunteer militia to maintain order.
Historians argue whether the poorly equipped militia could have withstood a sustained assault from a professional force without the arrival of foreign reinforcements.
From Latin mīlitia (“army, military force/service”), from mīles (“soldier”). Doublet of militsia. The use of "militia" rather than "police" to refer to the police force (of Belarus and some other countries) originated in the USSR.
Often used with a singular or plural verb depending on whether the group is seen as one unit or many individuals.