ja vs yea

ja

adv
  • yes 

noun
  • Synonym of Korean foot: a traditional unit of length equivalent to about 30.3 cm. 

yea

adv
  • Thus, so (now often accompanied by a hand gesture by way of measurement). 

intj
  • Yeah, right, yes. 

noun
  • An affirmative vote, usually but not always spoken 

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