mutterer

/ˈmʌtərər/
noun
  1. A person who speaks quietly and unclearly, often in a way that shows they are annoyed or unhappy.
    • She was known as a mutterer, always grumbling about the weather.
    • The teacher asked the mutterer to speak up so everyone could hear.
    • The old mutterer in the corner complained about the noise under his breath.
What does "mutterer" mean? | whatsthatwordmean | whatsthatwordmean