guerrilla

 
Pronunciation: /gəˈrɪlə/
(also guerilla)

noun

  • a member of a small independent group taking part in irregular fighting, typically against larger regular forces: this town fell to the guerrillas [as modifier]: guerrilla warfare
  • [as modifier] referring to actions or activities performed in an impromptu way, often without authorization: guerrilla gigs

Origin:

early 19th century (introduced during the Peninsular War): from Spanish, diminutive of guerra 'war'

Spelling help

Guerrilla can also be spelled guerilla, with a single r; both are correct.

Do not confuse gorilla with guerrilla. A gorilla is a type of large ape, whereas a guerrilla is a member of an independent group fighting against government or other regular forces ( he was held hostage by separatist guerrillas).