whistler

From Middle English whisteler, whistlar, whystelare, from Old English hwistlere (“a player on a flute; a piper”), equivalent to whistle +‎ -er.

whistler (plural whistlers)

1. Someone or something that whistles, or who plays a whistle as a musical instrument.
2. A bird that whistles (applied regionally to various specific species).
   • 1590, Edmund Spenser, The Faerie Qveene. […], London: Printed [by John Wolfe] for VVilliam Ponsonbie, OCLC 960102938, book II, canto XII:

     The lether-winged Bat, dayes enimy, / The ruefull Strich, still waiting on the bere, / The Whistler shrill, that who so heares, doth dy […]

3. The whistling marmot.
4. The goldeneye.
5. The mountain beaver.
6. An audio-frequency electromagnetic wave produced by atmospheric disturbances such as lightning.
7. A broken-winded horse.
8. (slang, obsolete) The keeper of a whistling shop, or shebeen.

• (whistling marmot): hoary marmot

• whirtles