border vs underpart

border

noun
  • The outer edge of something. 

  • A string that is both a prefix and a suffix of another particular string. 

  • A strip of ground in which ornamental plants are grown. 

  • border morris or border dancing; a vigorous style of traditional English dance originating from villages along the border between England and Wales, performed by a team of dancers usually with their faces disguised with black makeup. 

  • The line or frontier area separating political or geographical regions. 

  • A decorative strip around the edge of something. 

verb
  • To approach; to come near to; to verge (with on or upon). 

  • To put a border on something. 

  • To form a border around; to bound. 

  • To touch at a border (with on, upon, or with). 

  • To lie on, or adjacent to, a border of. 

underpart

noun
  • A lower or underneath part 

verb
  • To divide (a part) and assign subordinate portions of it. 

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