karabiner vs carabiner

karabiner and carabiner both are nouns.

Word	Noun	Adjective	Verb	Adverb
karabiner	Yes	No	No	No
carabiner	Yes	No	No	No

As nouns, karabiner and carabiner are synonyms defined as:

karabiner and carabiner: an oblong metal ring with a spring clip; used in mountaineering to attach a rope to a piton or to connect two ropes

Other synonyms of karabiner include snap ring.

karabiner (noun)	carabiner (noun)
an oblong metal ring with a spring clip; used in mountaineering to attach a rope to a piton or to connect two ropes	an oblong metal ring with a spring clip; used in mountaineering to attach a rope to a piton or to connect two ropes