Definition of ninja
: a person trained in ancient Japanese martial arts and employed especially for espionage and assassinations
Did You Know?
Ninjas may seem mysterious, but the origin of their name is not. The word ninja derives from the Japanese characters "nin" and "ja." "Nin" initially meant "persevere," but over time it developed the extended meanings "conceal" and "move stealthily." In Japanese, "ja" is the combining form of sha, meaning "person." Ninjas originated in the mountains of Japan over 800 years ago as practitioners of ninjutsu, a martial art sometimes called "the art of stealth" or "the art of invisibility." They often served as military spies and were trained in disguise, concealment, geography, meteorology, medicine, and also other martial arts. Popular legends still associate them with espionage and assassinations, but modern ninjas are most likely to study ninjutsu to improve their physical fitness and self-defense skills.
Origin and Etymology of ninja
Japanese, from nin- persevere, conceal, move stealthily + -ja person
First Known Use: 1964
NINJA Defined for English Language Learners
Definition of ninja for English Language Learners
: a fighter who is trained in the Japanese martial arts
NINJA Defined for Kids
Definition of ninja for Students
: a person trained in ancient Japanese martial arts who works as a spy and assassin especially in the past
Seen and Heard
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