sibilate

sibilate
    v 1: pronounce with an initial sibilant
    2: utter a sibilant
    3: express or utter with a hiss [syn: {hiss}, {sizz}, {siss},
       {sibilate}]
    4: make a sharp hissing sound, as if to show disapproval [syn:
       {hiss}, {siss}, {sizz}, {sibilate}]
    

Sibilate \Sib"i*late\, v. t. & i.
   To pronounce with a hissing sound, like that of the letter s;
   to mark with a character indicating such pronunciation.
   [1913 Webster]
    

84 Moby Thesaurus words for "sibilate":
      assibilate, bark, bawl, bellow, blare, blat, blubber, boom, bray,
      breathe, buzz, cackle, chant, chirp, coo, crow, drawl, effervesce,
      exclaim, fizz, fizzle, flute, gasp, growl, grunt, hiss, hush, keen,
      lilt, lisp, mumble, murmur, mutter, pant, pipe, roar, rumble,
      scream, screech, shriek, shush, sigh, sing, siss, sizz, sizzle,
      snap, snarl, sneeze, sniff, sniffle, snore, snort, snuff, snuffle,
      sob, spit, splutter, sputter, squall, squash, squawk, squeal,
      squelch, squish, swish, thunder, trumpet, twang, wail, warble,
      wheeze, whine, whish, whisk, whisper, whistle, whiz, whoosh, yap,
      yawp, yell, yelp, zip