biped vs humanoid

biped

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

humanoid

noun
  • A being having the appearance or characteristics of a human. 

adj
  • Having the appearance or characteristics of a human; being anthropomorphic under some criteria (physical, mental, genetical, ethological, ethical etc.). 

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