fly-by-night vs fugitive

fly-by-night

noun
  • One who departs or flees at night in order to avoid creditors, law enforcement etc. 

  • A traveling businessman or tradesman. 

  • A creature which flies at night; a nocturnal flier or traveler. 

  • A person or business that appears and/or disappears rapidly, appearing untrustworthy, or giving an impression of transience. 

fugitive

noun
  • A person who flees or escapes and travels secretly from place to place, and sometimes using disguises and aliases to conceal his/her identity, as to avoid law authorities in order to avoid an arrest or prosecution; or to avoid some other unwanted situation. 

adj
  • Elusive or difficult to retain. 

  • Fleeing or running away; escaping. 

  • Transient, fleeting or ephemeral. 

How often have the words fly-by-night and fugitive occurred in a corpus of books? (source: Google Ngram Viewer )