noun
ninja; shinobi
Historical term for a covert agent in feudal Japan, synonymous with 忍者. Often used in period pieces or traditional contexts.
See also: 忍者
忍びの者は夜陰に紛れて城に潜入した。
The ninja infiltrated the castle under cover of darkness.
忍者 is the more common modern term for ninja. 忍びの者 is a more traditional or literary expression.
Compound of 忍び (stealth, sneaking) + の (possessive particle) + 者 (person). Literally 'person of stealth'.