at home vs nonformal

at home

prep
  • At ease; comfortable. 

  • Playing at its usual venue, playing as the home team. 

  • Used other than figuratively or idiomatically: see at, home. In one's place of residence. 

  • In the home of one's parents. 

noun
  • A type of reception or party whereby the host says they will be ‘at home’ during specific hours, when guests can come and go as they like. 

nonformal

adj
  • Not formal. 

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