1) One of the species of martens, but used loosely in more recent times for any animal of the genus <i>Mustela</i>, including ferrets and stoats (OED).
1731 I called at Burnley [Burn Lee] ... to look at a wild dog which ... they took for a Martin and hunted it often before they could take it, New Mill. The fur of martens was prized in the Middle Ages and huge amounts were imported: 1424 unam togam nigram furruratam cum marterenz, Bawtry
1446 et meam optimam togam furruratam cum martes, Roche
1453 1 tymbre marterns
1463 3 martskynnes
1471 10 martfelles, Hull
1508 j toga scarleta penulata cum lez martrons, York.