Guerrilla (noun)

1. A member of a small independent group taking part in irregular fighting, typically against larger regular forces.
2. A type of warfare or tactics in which a small group uses unconventional and mobile methods, such as ambushes and raids, to disrupt a larger and less mobile opponent.

Origin:

Spanish, "little war", diminutive of guerra "war".

Examples:

1. The guerrilla fighters launched a surprise attack on the enemy camp.
2. The guerrilla campaign was long and difficult but ultimately successful.
3. The guerrilla tactics were used to great effect during the war.
4. The guerrilla fighters were highly motivated and dedicated to their cause.
5. The guerrilla warfare was characterized by its hit-and-run tactics.