い
　
っ
　
た
　
ん

adverb

Usually written with kana alone.
  1. once.
  2. for a short time, briefly, temporarily.

noun

Archaism.
  1. one morning.

Variations

Pronunciation Kanji Kana Is Common
　
い
　
っ
　
た
　
ん
 いったん ✔
いっ
一
たん
旦
 一旦 いったん ✔