facetiously vs seriously

facetiously

adv
  • In a facetious or flippant manner; in a manner that treats serious issues with deliberately inappropriate humor 

seriously

adv
  • Used to attempt to introduce a serious point in a less serious conversation. 

  • In a serious or literal manner. 

  • In an extreme or major way; majorly 

  • Used to call back to a previous point, in disbelief or for emphasis. 

  • Gravely; deeply; very much. 

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