blackball vs invaginate

blackball

verb
  • To ostracize. 

  • To vote against, especially in an exclusive organization. 

noun
  • A black ball used to indicate such a negative vote. 

  • A rejection; a vote against admitting someone. 

  • A kind of large black sweet; a niggerball. 

  • A game, a standardized version of the English version of eight-ball. 

  • A substance for blacking shoes, boots, etc. or for taking impressions of engraved work. 

invaginate

verb
  • To turn or fold inwardly. 

  • To fold inward to create a hollow space where none had existed, as with a gastrula forming from a blastula. 

  • To fold up or enclose into a sheath-like or pouch-like structure, either naturally or as part of a surgical procedure. 

adj
  • Having one portion of a hollow organ drawn back within another portion. 

  • sheathed 

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