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to shut oneself in (e.g. one's room); to be confined in; to seclude oneself; to hide away; to stay inside (one's shell)
to fill with (emotion, enthusiasm, power, etc.); to imbue with; to infuse with
to fill a space (of a gas, smell, etc.); to be heavy with (e.g. smoke); to be stuffy; to be dense
to be muffled (e.g. voice)
to hold (a castle, fortress, etc.)
to confine oneself in a temple to pray
彼は部屋に籠もって勉強している。
He is shut up in his room studying.
彼の声には深い感情が籠もっていました。
His voice was filled with emotion.
山奥に籠もって厳しい修行をしました。
I secluded myself deep in the mountains to train.