The root is attested also in HU: Ur. arc̣ib/wǝ 'name of a horse = Eagle' (see Diakonoff-Starostin 1986, 45). There is little doubt that all the listed forms belong together, although there are some problems. Not quite clear is the status of the prefixed syllable *ʔār-, attested in PN, HU, Lak., PD and PL. It should be noted that the Lak., PD (and possibly PL > Ag) forms reflect a variant with metathesized labialisation (*ʔār-c̣_wämʔV̆ > *ʔwār-c̣_ämʔV̆ ); in PL additionally the nasalisation was also shifted to the initial position. Quite irregular (and as yet unexplained) is -č̣- (instead of expected -c̣-) in PD (Chir.); however, there is no reason to suspect a borrowing. We should note also an interesting form: Cham. ercim 'kite'; since it is quite isolated within Av.-And., it must be an old Nakh borrowing (before the denasalisation *-mʔ- > -w-).