The most common Korean word for “once” is 한번 (hanbeon). 「once」는 한국어로 한번.
Learn 한번 free — flashcards, audio and review →「한번」 단어장으로 무료로 외우기Words and levels: TOPIK I essentials (National Institute of Korean Language standard curriculum, KOGL Type 1) · examples: Cheesepotato