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