The etymology of Proto-MSA *ˁar ‘but’ is uncertain. A cognate relationship with Arb. γayr- is rather attractive, but ˁ instead of γ is hard to explain. (Kogan 2015:549)
Proto-MSA
*ˁ/ˀardīb - nape of the neck and the top of the shoulders
(SED I 44, Kogan 2015:549–550)
The origin is uncertain. Compare probably with Arb. ˁšw ‘to repair, to betake oneself by night’. Cf. also Tgr. ˁassä ‘to fly; to run quickly’ as well as Akk. ašāšu ‘to be worried’. (Kogan 2015:550)
Proto-MSA *bV ‘here’ has often been identified with Hbr. pō with the same meaning, but the consonantal irregularity remains unexplained (Kogan 2015:550)