Compounds of 三

• 遊蕩三昧
  (n) being absorbed in self-indulgent pleasures
  giving oneself up to debauchery and dissipation
• 冷汗三斗
  (n) breaking into cold sweat when one is very embarrassed or scared
• 労働三法
  (n) the three labor laws (trade union law, labor standards law, labor relations adjustment law) (labour)
• 六韜三略
  (n) two books on the art of war in ancient China
  the secrets (essence) of the art of war
  secrets of successful life
  precepts for living
• 狡兎三窟
  (n) very shrewd in preparing a means of escape
  being very good at escaping danger
• 贅沢三昧
  (n) indulging in every possible luxury
• 韋編三絶
  (n,vs) repeated reading
  close (careful) reading
  careful perusal
• オート三輪
  (n) three-wheeler vehicle
• 鋭角三角形
  (n) acute triangle
• 逆三角関数
  (n) (math) inverse trigonometric function
• 球面三角法
  (n) spherical trigonometry
• 結びの三番
  (n) final three bouts of the tournament day (sumo)
• 向こう三軒
  (n) one's next three neighbors
  one's next three neighbours
• 降三世明王
  (n) (Buddh) Trailokyavijaya Vidya-raja
  conqueror of the three worlds
• 三井寺芥虫
  (n) (uk) Pheropsophus jessoensis (species of bombardier beetle)
• 三角形集合
  (n) (comp) triangle set
• 三角系異常
  (n) (math) triangle anomaly
• 三月の節句
  (n) Girls' (dolls') Festival (March 3rd)
• 三行広告欄
  (n) classified ads
• 三項演算子
  (n) ternary operator
  conditional operator
• 三叉神経痛
  (n) trigeminal neuralgia
• 三酸化硫黄
  (n) sulfur trioxide (SO3)
• 三次元映画
  (n) (obsc) 3D movie
• 三尺の秋水
  (n) sharpened sword
• 三尺の童子
  (n) mere child
• 三種の神器
  (n) the Three Sacred Treasures (Mirror, Sword and Jewels)
• 三秋の思い
  (n) longing for loved ones
• 三十年戦争
  (n) the Thirty Years' War
• 三十八度線
  (n) the Thirty-eighth Parallel
  (P)
• 三色スミレ
  (n) heartsease (wild pansy, Viola tricolor)