noun
long-armed; having long arms
Literally describes someone or something with long arms. Also used figuratively for a person who steals things, as if their arms can reach anywhere.
手長猿は腕がとても長い。
The long-armed ape has very long arms.
彼は手長で、よく人の物を盗む。
He is a kleptomaniac and often steals other people's things.
盗癖 is a more clinical term for kleptomania, while 手長 is a colloquial and somewhat old-fashioned expression.
Compound of 手 (hand/arm) and 長 (long). The figurative meaning 'kleptomaniac' comes from the image of having long arms that can reach and take things.