customary vs humdrum

customary

noun
  • A book containing laws and usages, or customs; a custumal. 

adj
  • In accordance with, or established by, custom or common usage 

  • Holding or held by custom 

humdrum

noun
  • The quality of lacking variety or excitement. 

adj
  • Lacking variety or excitement; dull; boring. 

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