noun
arm glove; arm warmer
A tubular garment worn on the forearm, often knitted, for warmth or fashion. Similar to a fingerless glove but without hand coverage.
寒い日は腕袋をしてパソコン作業をします。
On cold days, I wear arm warmers while working on the computer.
彼女は手編みの腕袋をプレゼントしてくれた。
She gave me hand-knitted arm warmers as a present.