From Sino-Korean 生覺 — though now fully nativized in feel and usage, the characters literally meant "to give rise to awareness." In modern Korean the word functions as a versatile everyday noun and is also the root of the verb 생각하다 (to think).

생각 is one of the most flexible words in Korean. It can mean a passing thought ("그런 생각은 못 했어" — "I hadn't thought of that"), a plan or intention ("갈 생각이 없어" — "I have no intention of going"), or a memory/longing ("네 생각이 나" — "I'm thinking of you / I miss you"). That last nuance — using 생각 to express missing someone — often surprises learners coming from English.