hiss

Verb/Noun
  1. To make a sharp sibilant sound, often as a sign of displeasure or warning. Verb/Noun
    The snake hissed loudly.
  2. A sound like a prolonged s, made by something hot or compressed air escaping. Verb/Noun
    The radiator emitted a steady hiss.
synonyms: sizzle, steam, whistle, sibilant sound