shallow vs superficial

shallow

adj
  • Lacking interest or substance. 

  • 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. 

noun
  • A costermonger's barrow. 

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

  • A fish, the rudd. 

verb
  • To make or become less deep. 

superficial

adj
  • Lacking depth of character or understanding; lacking substance or significance. 

  • Not thorough, deep, or complete; concerned only with the obvious or apparent. 

  • Existing, occurring, or located on the surface. 

  • Appearing to be true or real only until examined more closely. 

  • Situated or occurring on the skin or immediately beneath it. 

  • Two-dimensional; drawn on a flat surface. 

  • Denoting a quantity of a material expressed in terms of area covered rather than linear dimension or volume. 

noun
  • A surface detail. 

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