KARABINER

n. oblong metal ring used in mountain and rock climbing

This article is about the climbing and safety hardware. For the weapon, see carbine. For the cavalry soldier, see CarabinierA carabiner or karabiner (colloquially: crab, d ring, krab, or 'biner) is a metal loop with a sprung or screwed gate. It can quickly and reversibly connect components in safety-critical systems. The word comes from "Karabinerhaken", meaning "hook for a carbine" in German.
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Noun
1. an oblong metal ring with a spring clip; used in mountaineering to attach a rope to a piton or to connect two ropes
(synonym) carabiner, snap ring
(hypernym) hoop, ring

n. carbine, firearm, gun

SNAP HOOK
A metal fitting with a arm that uses a spring to close automatically when connected to another object.