biped vs human

biped

noun
  • An animal, being or construction that goes about on two feet (or two legs). 

human

noun
  • The tallest, most abundant and most intelligent of primates; Homo sapiens. 

  • Any hominid of the genus Homo. 

verb
  • To behave as or become, or to cause to behave as or become, a human. 

adj
  • Of or belonging to the species Homo sapiens or its closest relatives. 

  • Having the nature or attributes of a human being. 

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