mega vs unbelievingly

mega

adv

  • extremely 

adj

  • Great; excellent. 

  • Very large. 

noun

  • The Steinhaus-Moser number ② 

unbelievingly

adv

  • Synonym of incredibly 

  • In an unbelieving way. 

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