antechamber vs thalamus

antechamber

noun
  • A small room used as an entryway or reception area to a larger room. 

thalamus

noun
  • An inner room or nuptial chamber. 

  • The receptacle of a flower; a torus. 

  • A thallus. 

  • Either of two large, ovoid structures of grey matter within the forebrain that relay sensory impulses to the cerebral cortex. 

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