A paramilitary is a force whose function and organization are similar to those of a professional military, but which is not considered part of a state's formal armed forces.[1]

The term paramilitary is subjective, depending on what is considered similar to a military force, and what status a force is considered to have. The nature of paramilitary forces therefore varies greatly according to the speaker and the context.

For instance, in Northern Ireland, paramilitary refers to any illegal armed group with a political purpose, but in Colombia, paramilitary refers only to illegal armed right-wing groups (such as the United Self-Defense Forces of Colombia) that are not in direct opposition to the government, while illegal armed left-wing groups rebelling against the government (such as Revolutionary Armed Forces of Colombia) are referred to as guerrillas.[2]