From WordNet (r) 3.0 (2006) [wn]:
warrior
n 1: someone engaged in or experienced in warfare
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Warrior \War"rior\ (?; 277), n. [OE. werreour, OF. werreour,
guerreor, from guerre, werre, war. See War, and Warray.]
A man engaged or experienced in war, or in the military life;
a soldier; a champion.
[1913 Webster]
Warriors old with ordered spear and shield. --Milton.
[1913 Webster]
Warrior ant (Zool.), a reddish ant (Formica sanguinea)
native of Europe and America. It is one of the species
which move in armies to capture and enslave other ants.
[1913 Webster]