ظَهْرَكَ

ظَهْرَكَ is a phrase (شِبْهُ الجُمْلَةِ) consisting of a possessed noun and an attached, second-person, singular, possessive pronoun

PhraseNoun / NounNoun Noun
شِبْهُ الجُمْلَةِمُضَافٌ وَ مُضَافٌ إِلَيْهِمُضَافٌ إِلَيْهِمُضَافٌ
PhrasePossessive compoundPossessive noun/ownerNoun possessed/owned
back of yoursظَهْرَكَ=كَ+ظَهْرَ
your backyoursback of
Surah/Below is the only verse in the holy Quran containing the nominal compoundظَهْرَكَ
Verse
94-3Which weighed down your backالَّذِى أَنْقَضَ ظَهْرَكَ