• noun:   a schwa that is incidental to the pronunciation of a consonant
• noun:   a complaint uttered in a low and indistinct tone
• noun:   a low continuous indistinct sound; often accompanied by movement of the lips without the production of articulate speech
• noun:   an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves
• verb:   make complaining remarks or noises under one's breath
• verb:   speak softly or indistinctly

  Example: "She murmured softly to the baby in her arms"

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