same vs underside

same

pron
  • It or them, as above, meaning the last object mentioned, mainly as complement: on the same, for the same. 

  • It or them, without a connotation of similarity. 

  • The identical thing, ditto. 

  • Something similar, something of the identical type. 

adj
  • Similar, alike. 

  • Used to express the unity of an object or person which has various different descriptions or qualities. 

  • Lacking variety from; indistinguishable. 

  • Not different or other; not another or others; not different as regards self; selfsame; identical. 

  • A reply of confirmation of identity. 

intj
  • Indicates the speaker's strong approval or agreement with the previous material. 

adv
  • The same way; in the same manner; to the same extent, equally. 

underside

noun
  • The side that is below or underneath, the bottom. 

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