PS

*ṯVn(n)- - crotch, groin (Kogan/Militarev 2002: 317–318; Kogan 2011: 218)

Akkadian
sūnu - lap, crotch (CAD S 386, AHw. 1059)
Arabic
ṯunnat- - lower part of the belly, the pubes (BK 1 238, Lane 365)
Harari
šān - groin (EDH 146)