는 거 말다

not that one — something else

The 말고 form rules out what came just before it: 네가 좋아하는 거 말고 "not the one you like", 같이 나가는 거 말고 "not going out together". Add -도 and it stops excluding and starts adding: 먹는 거 말고도 잘하는 거 "things she's good at besides eating". This is 말다 in its "no, not that" sense; the same verb as a command — 하지 마 — is the one meaning "don't".

Register: casual spoken