PWS

*ˁaṣay- - coccyx, backbone (SED I No. 23; Kogan 2011: 218)

Vocalism tentative.

Hebrew
ˁāṣē - coccyx (HALOT 866)
Jewish Palestinian Aramaic
ˁyṣy - backbone (DJPA 405)
Arabic
ˁaṣaṣ-, ˁuṣuṣ-, ˁuṣˁūṣ- - caudal bone of the tail (BK 2 272, Lane 2057)
Related with reduplication.
Arabic
ˁaṣan - bone of the shank (BK 2 275, Lane 2069)
Tigre
ˁeṣat - back (of men and animals); loin(s), waist (WTS 491)
poet. ˁəṣet, pl. ˁawäṣṣi, ˁaṣäṣṣi