What you mentioned are the two primary meanings of 담다. The original meaning of 담다 is to put or place something in a container ("쌀통에 쌀을 담다", "그릇에 가득 담은 음식"). The other meaning 표현하다 is an extension of this base meaning, in the sense that an expression is an act of projecting (or even placing) our feelings onto or in some medium, like a word, drawing, tune, or whatever. 담다 in this sense is thus usually used together with the medium of expression. For example, - 맘을 담은 편지 => a letter that conveys someone's feelings = a letter that bears/contains someone's feelings. - 그의 고별 연설은 10년의 역사를 담아냈다 => His farewell speech bore out the history of the past ten years. (담아내다 = 담다 + -내다(does all the way). -내다 emphasizes that it has done it thoroughly) Using 담다 without the medium can sound strange. - 그는 울분을 담았다 (weird sentence - place the anger and frustration where?) - 그는 울분을 토해냈다/표현했다/표출했다/토로했다. (natural - these words don't need the medium) 담다 is also used in the sense of "keep in one's mind" or "dwell on (negative thoughts)" - again an extension of put/place. - 그 충고의 말씀 가슴에 잘 담겠습니다 = I'll always keep your valuable advice in my mind. - 걔가 한 말 마음에 담지 마 [담아두지 마] = Don't dwell on what he/she said = Don't put that in your mind.