mutter

/ˈmʌtər/
noun
  1. A quiet, unclear utterance or a low sound of complaint.
    • His reply was barely a mutter, so I asked him to speak up.
    • I heard a mutter from the back of the room.
    • There was a mutter of discontent among the crowd.
Synonyms
verb
  1. To speak quietly and unclearly, often in a way that is difficult to hear or understand.
    • She muttered an apology, but no one could hear her.
    • The old man muttered to himself while reading the newspaper.
    • He muttered something under his breath as he walked away.
  2. To complain or grumble in a low, quiet voice.
    • The workers muttered about the long hours and low pay.
    • She muttered complaints about the cold weather all morning.
    • The students muttered among themselves when the teacher gave extra homework.
Antonyms
What does "mutter" mean? | whatsthatwordmean | whatsthatwordmean