ninja
In real, traceable use. Part of the curated seed collection; community review is coming.
Sense 1
One trained in ninjutsu, especially one used for espionage, assassination, and other tasks requiring stealth during Japan's shogunate period.
Examples
Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Sense 2
One who very skillful, considered similar to the historical ninja, especially in covert or stealthy operation.
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Sense 3
One who very skillful, considered similar to the historical ninja, especially in covert or stealthy operation. — A notional draconian arm of a corporation (originally Nintendo), tasked with dealing with individuals that infringe on its rights or do not comply with its regulations.
Register: slang
Sources & notes
Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).
Common questions
What does “ninja” mean?
One trained in ninjutsu, especially one used for espionage, assassination, and other tasks requiring stealth during Japan's shogunate period.
Is “ninja” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.