gudgeon vs trunnion

gudgeon

noun
  • A circular or cylindrical fitting, often made of metal, into which a pin or pintle fits to create a hinge or pivoting joint. 

  • A small freshwater fish, Gobio gobio, that is native to Eurasia. 

  • Any of various similar small fish of the family Eleotridae, often used as bait. 

  • In a vessel with a stern-mounted rudder: the fitting into which the pintle of the rudder fits, allowing the rudder to swing freely. 

  • Other fish, similar in appearance, principally in families Butidae and Eleotridae, but also in others. 

  • Cottus bairdii, more widely known as mottled sculpin. 

trunnion

noun
  • A similar rotational bearing comprising a rotating arc or ring sliding in the groove of a stationary arc, used in machinery to allow a workpiece to be moved relative to a fixed tool. 

  • A similar rotational bearing used in automotive suspensions. 

  • A shaft, held by a bearing, at each end or side of a rotatable object. 

  • One of the short stubby bearings on either side of a cannon; a gudgeon. 

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