Vocabulary What does 母乳 (ぼにゅう, bonyuu) mean? 母乳 (ぼにゅう, bonyuu) means mother's milk. Quick factsReadingぼにゅうRomajibonyuuPart of speechnoun 母乳ぼにゅうbonyuumother's milk1noun mother's milkKanji in this word母mother乳milk; breast