n. pl. ninja or nin·jas
A member of a class of medieval Japanese mercenary agents who were trained in the martial arts and hired for covert operations such as assassination and sabotage.
[Japanese : nin, to endure (from Early Middle Chinese ᶮin'; also the source of Mandarin rěn) + sha, person (from Middle Chinese tʂia´, pronoun for head of a relative clause; also the source of Mandarin zhě).]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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