In this ideograph, the symbol for day is combined with a point of light. The point of light marks the transition from night to day at the summer solstice, when the sun rises in the northeast.
Hence, this is the noun summer solstice or midsummer day.
Illustrative Text Reference:
Nausharo: Seal: NS-6 A (There is no view a): Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 408: Collections in Pakistan: Suomalainen
Midsummer Day (a modified version of Mahadevan's sign number 293): Lynn Fawcett, 2017.