PC

*γār- - (loose) skin, dewlap (SED I No. 106; Kogan 2011: 216)

has no etymology

Akkadian
āru - hide (?) (CAD a₂ 318)
Under a question. In [AHw. 72] it is interpreted as ‘Kalb’ with a question mark
Ugaritic
γr - skin (DUL 325)
Phoenician
ˁr - skin (DNWSI 887)
Hebrew
ˁōr - skin (HALOT 803)
Jewish Palestinian Aramaic
ˁūr - husk, chaff (Jastrow 1058, DJPA 400b)
Also, ˀūrā ‘skin’ [ibid. 32], with ˀ- instead of ˁ-
Arabic
γarrat-, γurrat- - fold (of skin, of fabric) (BK 2 446)
Arabic
γarγarat-, γurγurat- - gizzard of bird (BK 2 457)
Mehri
γərγār, γərγərōt - side of throat (ML 141)
Jibbali
γɔrγɔ́rɔ́t, γarγɔ́rɔ́t - dewlap (JL 88)