ڛَادَق
ŝádaḳ (du. ŝádḳi, pl. ŝídaḳ)
basic morphological information

n. (m.)

corner of the mouth
уголок рта
شدق
CSOL I 664
text examples

ʸhes ḷe-ŝádaḳ máẓ̂aˁ ˁaf yeṭarɛ́boʰ meʸh ḥouľíľi di-ḥóʸhi ‘He put it in one corner of his mouth and tried to take a bite, and two of his dogteeth fell to the ground’ (CSOL I 2:51)

root
etymology

Also in Arb. šidq- ‘the quivering flesh of the mouth, inside the two cheeks’, Mhr. ŝadḳ ‘inside of the cheek, from and including the corner of the mouth’, Jib. ŝɛdḳ id.. An Arabism in MSA is not unlikely.