en plein air vs outwith

en plein air

adv
  • in the open air, alfresco, outside, outdoors 

adj
  • in the open air, alfresco, outside, outdoors 

outwith

adv
  • Outside, outwardly; outwards. 

prep
  • Outside; beyond; outside of. 

How often have the words en plein air and outwith occurred in a corpus of books? (source: Google Ngram Viewer )