to shut oneself in (e.g. one's room); to be confined in; to be filled with (emotion, enthusiasm, etc.); to fill the room (of a gas, smell, etc.); to be heavy with (e.g. smoke); to be muffled (e.g. voice); to hold (a castle, fortress, etc.)
Examples (2 in total)
しかし王女は部屋にたてこもって出てこなかった。
However, the princess had barricaded herself in her room and wouldn't come out.