Vocabulary
一瞬にして
いっしゅんにして
in an instant; instantly; in a moment; instantaneously; in the twinkling of an eye
expression
adverb
Example sentences
苦心惨憺（くしんさんたん）の末（すえ）、考え出（かんがえだ）した企画（きかく）が、会議（かいぎ）で一瞬（いっしゅん）にして却下（きゃっか）されちゃうんだからな。
After all the trouble we went to in coming up with that project, it only took them a second to shoot it down in the meeting.