Denshi Jisho — Online Japanese dictionary

一瞬 いっしゅん moment; instant
Common word, Adverbial noun, Temporal noun 
一瞬 いっしゅんかん moment; instant
Noun 
一瞬絶句 いっしゅんぜっく breaking off short (in one's speech); rendered speechless for a moment
Noun, Suru verb 

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