shallow vs shoal

shallow

noun
  • A shallow portion of an otherwise deep body of water. 

  • A costermonger's barrow. 

  • A fish, the rudd. 

verb
  • To make or become less deep. 

adj
  • Not steep; close to horizontal. 

  • Not far forward, close to the net. 

  • Having little depth; significantly less deep than wide. 

  • Not intellectually deep; not penetrating deeply; simple; not wise or knowing. 

  • Concerned mainly with superficial matters. 

  • Extending not far downward. 

  • Lacking interest or substance. 

shoal

noun
  • A shallow in a body of water. 

  • A sandbank or sandbar creating a shallow. 

  • A large number of fish (or other sea creatures) of the same species swimming together. 

  • Any large number of persons or things. 

verb
  • To become shallow. 

  • To arrive at a shallow (or less deep) area. 

  • To collect in a shoal; to throng. 

  • To cause a shallowing; to come to a more shallow part of. 

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