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胸三寸 (むねさんずん) Japanese meaning | Kotomora
Meanings 1
noun
heart ; mind ; feelings
Idiomatic expression referring to one's inner thoughts, emotions, or true intentions, literally 'three inches inside the chest'. Often used in set phrases like 胸三寸に納める (keep to oneself) or 胸三寸で決まる (be decided by one's heart).
成せい 功こう する か どう か は 、 結けっ 局きょく は 胸むね 三さん 寸ずん で 決き まる 。
Whether you succeed or not ultimately depends on your state of mind.
Kanji 寸 measurement, tenth of a shaku, a little Similar words 胸きょう 中ちゅう 胸中 is a more formal, literary term for 'in one's heart/mind', while 胸三寸 is a colloquial, idiomatic expression with a similar meaning but a more vivid, physical image.
心こころ 心 is the general word for 'heart/mind/spirit'. 胸三寸 is a more figurative, set-phrase alternative emphasizing the hidden or decisive nature of one's inner thoughts.
Etymology Compound of 胸 (chest) and 三寸 (three sun, about 9 cm), literally 'three inches inside the chest'. The exact origin is uncertain, but it metaphorically refers to the seat of emotions and thoughts, similar to English 'heart of hearts'.