\Guer*ril"la\, n. [Sp., lit., a little war, skirmish,
dim. of guerra war, fr. OHG. werra discord, strife. See
{War}.]
1. An irregular mode of carrying on war, by the constant
   attacks of independent bands, adopted in the north of
   Spain during the Peninsular war.
2. One who carries on, or assists in carrying on, irregular
   warfare; especially, a member of an independent band
   engaged in predatory excursions in war time.
Note: The term guerrilla is the diminutive of the Spanish
      word guerra, war, and means petty war, that is, war
      carried on by detached parties; generally in the
      mountains. . . . A guerrilla party means, an irregular
      band of armed men, carrying on an irregular war, not
      being able, according to their character as a guerrilla
      party, to carry on what the law terms a regular war.
      --F. Lieder.

\Guer*ril"la\, a.
Pertaining to, or engaged in, warfare carried on irregularly
and by independent bands; as, a guerrilla party; guerrilla
warfare.