- 忍者【にんじゃ】 - ninja, person trained in ninjutsu and employed for covert purposes in feudal Japan 
- 忍び込む【しのびこむ】 - to creep in, to steal in, to sneak in 
- 忍耐【にんたい】 - endurance, perseverance, patience 
- 忍ぶ【しのぶ】 - to conceal oneself, to hide, to endure, to bear, to stand, to put up with 
- 残忍【ざんにん】 - brutal, cruel, merciless, ruthless, cold-blooded 
- 忍び寄る【しのびよる】 - to creep, to steal up, to draw near unnoticed 
- 堪忍袋【かんにんぶくろ】 - one's store of patience 
- 忍び【しのび】 - stealth, travelling incognito (traveling), ninjutsu, ninja, sneak theft, sneak thief, tolerance