migrant vs on the move

migrant

adj
  • Migratory. 

noun
  • A person who leaves one place in order to permanently settle in another. 

  • A migratory animal, in particular a migratory bird. 

  • Traveller or worker who moves from one region or country to another. 

  • Any of various pierid butterflies of the genus Catopsilia. Also called an emigrant. 

on the move

adj
  • Changing location; in motion 

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