1 عمومی:: زیر لب سخن گفتن، من من كردن
شبکه مترجمین ایران
1 general:: verb speak indistinctly: I could not understand him when he mumbled.
Simple Definitions
2 general:: verb ADV. incoherently | drowsily, sleepily PREP. about I couldn't understand what he was mumbling about. | into She mumbled something into her pillow. | to George mumbled incoherently to himself.
Oxford Collocations Dictionary