Yn is a letter of the old Romanian Cyrillic alphabet.
YN or Yn may also refer to: Yn (Georgian letter), an additional letter of the Georgian alphabet Yeoman (United States Navy), a rank A US Navy hull classification symbol: Yard net tender (YN) Yoctonewton, a unit of force equal to 10−24 newtons Yottanewton, a unit of force equal to 1024 newtons Triple bond, in a chemical compound 2C-YN, an analogue of the phenethylamine derived hallucinogen 2C-E Yes–no question Yunnan, a province of China (Guobiao abbreviation YN) Y/N, a 2023 novel by Esther Yi Yttrium nitride Your name, an abbreviation used in self-insert fan fiction