Ugaritic

ˀišd - leg (DUL 116, Watson 2007: 79)

cf. Akk. ˀišdu (Kogan 2015: 332)
it is debatable whether the word is related to PWS *šit- ‘buttocks’, see Kogan 2011: 218

*ˀišd - backside, lower leg, base, foundation (Kogan 2015: 204)

PWS *šit- ‘buttocks’ may be related, see Kogan 2011: 218