TT #85 · Parashas Noach · Seventh Aliyah · Passuk 11:29
Avram and Nachor took wives for themselves; the name of Avram’s wife was Sarai, and the name of Nachor’s wife was Milkah, the daughter of Haran, the father of Milkah and the father of Yiskah.
Torah Temimah points to the identification of Yiskah with Sarah (Sanhedrin 69b / Megillah).
E-Daf image — Sanhedrin 69b (size=3)
English: “Yiskah” — It was taught: Yiskah is Sarah. Why was she called Yiskah? Because she gazed (sachah) with the holy spirit… Alternatively: because everyone gazed upon her beauty.
Custom (identification of Yiskah with Sarah and dual etymology).
Yiskah is Sarah; the name alludes either to prophetic vision or to the universal admiration of her beauty.