The Collaborative International Dictionary of English v.0.48:

Whistle \Whis"tle\, v. i. [imp. & p. p. Whistled; p. pr. & vb.
   n. Whistling.] [AS. hwistlian; akin to Sw. hvissla, Dan.
   hvisle, Icel. hv[imac]sla to whisper, and E. whisper.
   [root]43. See Whisper.]
   [1913 Webster]
   1. To make a kind of musical sound, or series of sounds, by
      forcing the breath through a small orifice formed by
      contracting the lips; also, to emit a similar sound, or
      series of notes, from the mouth or beak, as birds.
      [1913 Webster]

            The weary plowman leaves the task of day,
            And, trudging homeward, whistles on the way. --Gay.
      [1913 Webster]

   2. To make a shrill sound with a wind or steam instrument,
      somewhat like that made with the lips; to blow a sharp,
      shrill tone.
      [1913 Webster]

   3. To sound shrill, or like a pipe; to make a sharp, shrill
      sound; as, a bullet whistles through the air.
      [1913 Webster]

            The wild winds whistle, and the billows roar.
                                                  --Pope.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Whistling \Whis"tling\,
   a. & n. from Whistle, v.
   [1913 Webster]

   Whistling buoy. (Naut.) See under Buoy.

   Whistling coot (Zool.), the American black scoter.

   Whistling Dick. (Zool.)
   (a) An Australian shrike thrush (Colluricincla Selbii).
   (b) The song thrush. [Prov. Eng.]

   Whistling duck. (Zool.)
   (a) The golden-eye.
   (b) A tree duck.

   Whistling eagle (Zool.), a small Australian eagle
      (Haliastur sphenurus); -- called also whistling hawk,
      and little swamp eagle.

   Whistling plover. (Zool.)
   (a) The golden plover.
   (b) The black-bellied, or gray, plover.

   Whistling snipe (Zool.), the American woodcock.

   Whistling swan. (Zool.)
   (a) The European whooper swan; -- called also wild swan,
       and elk.
   (b) An American swan (Olor columbianus). See under Swan.


   Whistling teal (Zool.), a tree duck, as Dendrocygna
      awsuree of India.

   Whistling thrush. (Zool.)
   (a) Any one of several species of singing birds of the genus
       Myiophonus, native of Asia, Australia, and the East
       Indies. They are generally black, glossed with blue, and
       have a patch of bright blue on each shoulder. Their note
       is a loud and clear whistle.
   (b) The song thrush. [Prov. Eng.]
       [1913 Webster]

WordNet (r) 3.0 (2006):

whistling
    n 1: the sound made by something moving rapidly or by steam
         coming out of a small aperture [syn: whistle,
         whistling]
    2: the act of whistling a tune; "his cheerful whistling
       indicated that he enjoyed his work"
    3: the act of signalling (e.g., summoning) by whistling or
       blowing a whistle; "the whistle signalled the end of the
       game" [syn: whistle, whistling]

Moby Thesaurus II by Grady Ward, 1.0:

74 Moby Thesaurus words for "whistling":
   acute, argute, assibilation, buzz, creaky, ear-piercing,
   effervescence, effervescing, fizz, fizzle, fizzling, frication,
   frictional rustling, hiss, hissing, howling, hush, hushing, keen,
   keening, lisp, penetrating, piercing, piping, reedy, rhonchus,
   screaky, screeching, screechy, sharp, shrieking, shrieky, shrill,
   shush, shushing, sibilance, sibilation, siffle, sigmatism, siss,
   sissing, sizz, sizzle, sizzling, sneeze, sneezing, sniff, sniffle,
   snore, snort, snuff, snuffle, spit, splutter, sputter, squash,
   squeaking, squeaky, squelch, squish, sternutation, stertor, swish,
   thin, ululant, wailing, wheeze, whining, whish, whistle,
   white noise, whiz, whoosh, zip