ninja

noun nin·ja \ˈnin-jə, -(ˌ)jä\

: a fighter who is trained in the Japanese martial arts

plural ninja also ninjas

Full Definition of NINJA

: a person trained in ancient Japanese martial arts and employed especially for espionage and assassinations

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Japanese, from nin- persevere, conceal, move stealthily + -ja person

First Known Use: 1964

NINJAS Defined for Kids

noun nin·ja \ˈnin-jə\

plural ninja also nin·jas

: a person trained in ancient Japanese martial arts who works as a spy and assassin especially in the past

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