trawl vs tug

trawl

verb
  • To fish from a slow-moving boat. 

  • To take (fish or other marine animals) with a trawl. 

  • To make an exhaustive search for something within a defined area. 

noun
  • A long fishing line having many short lines bearing hooks attached to it; a setline. 

  • A net or dragnet used for trawling. 

tug

verb
  • To tow by tugboat. 

  • To masturbate. 

  • To pull or drag with great effort. 

  • To pull hard repeatedly. 

noun
  • A dog toy consisting of a rope, often with a knot in it. 

  • A trace, or drawing strap, of a harness. 

  • A tugboat. 

  • An iron hook of a hoisting tub, to which a tackle is affixed. 

  • A sudden powerful pull. 

  • An act of male masturbation. 

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