gib · noun1
Unknown (14th century). Perhaps abbreviated from Gilbert, the name of the cat in the medieval fables of Reynard the Fox, Romaunt of the Rose, and so on.
gib · noun, verb2
Unknown (late 18th century).
gib · noun, verb3
Shortened from giblet.
gib · noun, verb4
From the trademark GIB, registered by Fletcher Building Holdings Limited, the major brand of plasterboard in New Zealand.
gib · verb, noun5
Etymology from Wiktionary, CC BY-SA 4.0.