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ムキになる (むきになる) Japanese meaning | Kotomora
Meanings 1
expression, godan verb (-ru)
get worked up ; take something too seriously ; get huffy
usually written using kana alone
Describes someone who becomes overly serious, irritated, or angry in response to a joke, teasing, or trivial matter. Often used when someone can't take a lighthearted comment and reacts defensively.
彼かれ は 負ま け ず 嫌ぎら い で 、 ゲーム に 負ま ける と ムキ に なる 。
He hates losing and gets seriously worked up when he loses a game.
Written forms ムキになる
kana-only spelling
Usually written in kana; katakana spelling is common and natural for this expression.
向む きになる
Kanji spelling is possible but rarely used; the kana form is strongly preferred.
Similar words 本ほん 気き になる 本気になる means to become serious in a genuine, committed way (e.g., about work or a relationship), while ムキになる implies an overreaction or defensiveness, often to something minor.
怒おこ る 怒る is a general verb for getting angry. ムキになる adds the nuance of being provoked by something trivial and reacting with excessive seriousness or irritation.
Etymology The origin is uncertain. It may be related to 向く (muku, 'to face/turn toward'), suggesting turning one's attention or attitude in a serious direction, but the exact derivation is unclear.
