undersee vs unheed

undersee

verb
  • To neglect; fail to see properly or adequately; turn a blind eye to; ignore. 

  • To see or look under or below; see below the surface of. 

  • To look intently into; examine; inspect. 

unheed

verb
  • To deliberately fail to heed or take notice of; disregard; ignore. 

noun
  • Inattention. 

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