Korean phrase
~만 아는 얘기야. ~ man a neun yae gi ya
Meaning
be something known only to ___
When to use it
It means that only certain people know something. It marks the information as private and may suggest not sharing it.
Example dialogue
이거 다른 친구들한테 말하면 안 돼? i geo ta reun chin gu deul han te mal ha myeon an twae
Is it okay if I tell the other friends?
응, 이건 우리 둘만 아는 얘기야. eung i geon u ri tul man a neun yae gi ya
Yeah, this is something only the two of us know.