Phoenician

ˀps - only (DNWSI 97)

PC
*ˀaps- - extremity (HALOT 79, DRS 29, Kogan 2015: 283)
as suggested by HALOT 79 and DRS 29, may be borrowed from Akk. apsû ‘cosmic subterranean water’, in its turn going back to Sum. abzu.