母音三角形 ぼいんさんかっけい Also written ぼいんさんかくけい Meanings Noun vowel triangle Kanji 母 mother. Read as ボ. 音 sound. Read as イン. 三 three. Read as サン. 角 angle. Read as カク. 形 shape. Read as ケイ. Jinuma: Japanese Dictionary · Word lists