bosorito
Saying something in a low, quiet voice, almost to oneself. A single utterance spoken so softly that others might miss it. More deliberate than boso-boso.
💡A student answering reluctantly — 'He bosorito muttered the answer.'
彼女はぼそりと「ごめん」と言った。
She bosorito muttered "sorry."
He ___ muttered "I knew it" under his breath.
彼は○○と「やっぱりね」とつぶやいた。