noun
The part of a garment that covers the arm.
このシャツは袖が長すぎる。
The sleeves on this shirt are too long.
寒かったので、袖を引っ張って手を隠した。
It was cold, so I pulled my sleeves down to cover my hands.
noun
wing; side section
Used for the side sections of a stage, desk, gate, or similar structure, likened to a sleeve.
役者は舞台の袖で出番を待っている。
The actor is waiting in the wings of the stage for his cue.
門の袖に小さな通用口がある。
There is a small side gate in the wing of the main gate.
noun
flap; dust jacket flap
Specifically the folded flap of a book's dust jacket. Often written in kana.
本のそでに著者のプロフィールが載っている。
The author's profile is printed on the flap of the book.
The kanji 袖 is composed of 衣 (clothing) and 由 (origin/cause), suggesting the part of clothing from which the arm emerges. The historical derivation is uncertain.