- See under ninja.
noun, plural nin·ja, nin·jas.
- (often initial capital letter) a member of a feudal Japanese society of mercenary agents, highly trained in martial arts and stealth (ninjutsu), who were hired for covert purposes ranging from espionage to sabotage and assassination.
- a person who is expert or highly skilled in a specified field or activity (often used attributively): marketing ninjas; ninja gamers.
noun plural -ja or -jas
- (sometimes capital) a person skilled in ninjutsu, a Japanese martial art characterized by stealthy movement and camouflage