belly vs fin

belly

noun
  • The lower fuselage of an airplane. 

  • The stomach. 

  • The main curved portion of a knife blade. 

  • The abdomen, especially a fat one. 

  • The part of anything which resembles (either closely or abstractly) the human belly in protuberance or in concavity; often, the fundus (innermost part). 

  • The womb. 

  • The hollow part of a curved or bent timber, the convex part of which is the back. 

verb
  • To swell and become protuberant; to bulge or billow. 

  • To cause to swell out; to fill. 

  • To position one’s belly; to move on one’s belly. 

fin

noun
  • A thin, rigid component of an aircraft, extending from the fuselage and used to stabilise and steer the aircraft. 

  • A hairstyle, resembling the fin of a fish, in which the hair is combed and set into a vertical ridge along the top of the head from about the crown to the forehead. 

  • A similar structure on the tail of a bomb, used to help keep it on course. 

  • The conning tower of a submarine. 

  • a five-pound (£5) note; the sum of five pounds. 

  • One of the appendages of a fish, used to propel itself and to manoeuvre/maneuver. 

  • An extending part on a surface of a radiator, engine, heatsink, etc., used to facilitate cooling. 

  • A sharp raised edge (generally in concrete) capable of damaging a roof membrane or vapor retarder. 

  • A device worn by divers and swimmers on their feet. 

  • The finish, the end 

  • A similar appendage of a cetacean or other marine animal. 

verb
  • To cut the fins from a fish, shark, etc. 

  • (Of a fish) to swim with the dorsal fin above the surface of the water. 

  • To swim in the manner of a fish. 

  • To provide (a motor vehicle etc) with fins. 

How often have the words belly and fin occurred in a corpus of books? (source: Google Ngram Viewer )