acumen vs capitulum

acumen

noun
  • A bony, often sharp, protuberance, especially that of the ischium. 

  • Quickness of perception or discernment; penetration of mind; the faculty of nice discrimination. 

  • A sharp, tapering point extending from a plant. 

capitulum

noun
  • A small protuberance on a bone which articulates into another bone to form a ball-and-socket joint. 

  • The head-like mouthpart apparatus of a tick, including the palpi, mandibles, and hypostome. 

  • A densely clustered inflorescence composed of a large number of individual florets arising from a platform-like base. 

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