됐거든

became, turned into

→ 되다

됐 Past tense + 거든 Explanatory sentence ending (you see; because)

verb · informal, past tense Rare #25,762

became, turned into The sentence-ending -거든 adds an explanatory tone, often like “you see”; before another clause, it can mean “because.”

KO: 나 이제 어른이 됐거든.

EN: I’ve become an adult, you see.

Conjugation of 되다

Past

Because it's basically a swimming pool outside now.

— The Great Flood (2025)

Whatever.

— 로렌스 애니웨이 (2012)