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to be bulky; to be unwieldy; to grow voluminous
冬服は嵩張るのでスーツケースに入らない。
Winter clothes are bulky and don't fit in the suitcase.
お土産が嵩張って持ち帰るのが大変だった。
The souvenirs were bulky and hard to carry back.
書類が嵩張るのでデジタル化を進めている。
Documents are bulky, so we are promoting digitalization.