This is the 3148th most frequent Korean word.
거란
"거란" refers to the Khitan, a nomadic people who established the Liao Dynasty in East Asia.
거란 is used as a contraction of '거라는,' indicating a question about an action or situation.
그는 어디로 떠난 거란 말인가?
Where did he go?
거란 is used as a shortened form of '것이라는,' giving emphasis to the statement.
어떤 일을 해야 할 거란 걸 알고 있어.
I know that it's something I have to do.
Here, '거란' refers to the historical Khitan people or state.