Other forms: leashes
A leash is the strap for holding a dog. Clipped to the collar, and wrapped once round the hand.
American English says leash and British English usually says lead, and both are entirely ordinary at home. The word has a strong figurative life, since keeping somebody on a short leash means allowing them very little freedom, and straining at the leash means being impatient to start. As a verb it means to restrain, and unleashing something is the opposite, which is why unleash is now much commoner than leash.
1nounleashA strap for restraining and guiding a dog.
“Dogs must be kept on a leash in the park.”
A leash is a loose thing. Old French lesse comes from Latin laxus, loose, so the word is named for the slack in it rather than for the restraint.
Middle English
leesshe
English, today
leash
Built from
From Middle English leesshe, leysche, lesshe, a variant of more original lease, from Middle English lees, leese, leece, lese, from Old French lesse (modern French laisse), either from Latin laxa, feminine form of laxus (“loose”) or, more probably, from a deverbal of Old French lesser, laissier, from Latin laxō (“loose”); compare lax. a doublet of laisse.
Etymology from Wiktionary, CC BY-SA