Noun

1. Open countryside, or an area of open countryside.
   • 1485, Sir Thomas Malory, Le Morte Darthur, Book V:

     Then the Romaynes followed faste on horsebak and on foote over a fayre champeyne unto a fayre wood.

   • 1605, William Shakespeare, King Lear, I.i:

     Of all these bounds even from this line to this, / With shadowy forests and with champaigns riched, / With plenteous rivers and wide-skirted meads, / We make thee lady.

Adjective

1. Pertaining to open countryside; unforested, flat.
   • 1603, John Florio, translating Michel de Montaigne, Essays, Folio Society 2006, vol. 1 p. 206:

     They are seated alongst the sea-coast, encompassed toward the land with huge and steepie mountains, having betweene both, a hundred leagues or thereabouts of open and champaine ground.