Brewer's: Ostringers, Sperviters, Falconers
Ostringers are keepers of goshawks and tercelles. Sperviters are those who keep sparrowhawks or muskets. Falconers are those who keep any other kind of hawk, being long-winged.
(Markham Gentleman's Academie, or Booke of S. Albans.)
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894