expression, noun
brief moment; blink of an eye
Refers to a very short time span, often used in literary or descriptive contexts. Similar to 瞬く間に (in the blink of an eye).
花火は瞬く間に消えてしまった。
The fireworks disappeared in the blink of an eye.
彼は瞬く間に問題を解決した。
He solved the problem in a brief moment.
一瞬 is a more common and neutral word for 'an instant', while 瞬く間 emphasizes the brevity with a literary feel.
あっという間 is a colloquial expression for 'in no time', whereas 瞬く間 is more formal and often used in written language.
Compound of 瞬く (matataku, 'to blink') and 間 (ma, 'interval'), literally 'the interval of a blink'.