Rotary engine or Wankel engine: An engine with a triangular shaped rotary piston moving inside an epitrochoidal housing. Invented by Dr. Wankel engine, it is also called Wankel engine. Related posts: Personnel Management Operative Functions Administrative Role of PM Competency HR Management Role Change Personnel Policies Personnel Procedures Appealed Policies Implied Policies Specific Policies Personnel records Research Pure research Personnel research Attitude or Opinion Survey Turnover Secondary research Applied research Personnel audit Read more articles Previous PostRocker arm Next PostRun on or Dieseling