both vs twain

both

conj
  • Including both of (used with and). 

det
  • Each of the two; one and the other; referring to two individuals or items. 

pron
  • Each of the two, or of the two kinds. 

twain

adj
  • twofold 

verb
  • To part in twain; divide; sunder. 

noun
  • pair, couple 

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