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口がイーってなる (くちがイーってなる) Japanese meaning | Kotomora
Meanings 1
expression, godan verb (-ru)
grin with closed teeth ; make a tight-lipped grin
colloquial
Colloquial expression describing a facial expression where the mouth stretches sideways into a tight grin, often when forcing a smile or holding back laughter. The 'イー' represents the sound of the mouth stretching.
笑わら い を こらえよう と し て 、 口くち が イー って なっ て しまっ た 。
Trying to hold back laughter, my mouth ended up in a tight-lipped grin.
Similar words にやける にやける describes a loose, often smirking or silly grin, while 口がイーってなる specifically refers to a tight, stretched grin with closed teeth.
口くち 元もと が 緩ゆる む 口元が緩む means the corners of the mouth relax into a smile, often involuntarily; 口がイーってなる emphasizes the sideways stretching and the sound 'イー'.
Etymology The expression is formed from 口 (mouth), the particle が, the onomatopoeic sound イー (representing the mouth stretching), the quotative particle って, and the verb なる (to become). It mimics the sound or sensation of the mouth pulling tight.
