This is a simple pictograph of an eye. It also has a second, ideographic reading as a point of light within an area, which again gives us an eye. The symbol shares a common root with the Chinese character mù 目. It is the verb to look, or to see.
Illustrative Text References:
Look: Mohenjo-daro: Seal: M-1369 a: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 179: Collections in Pakistan: Suomalainen Tiedeakatemia.
Look: Mohenjo-daro: Tablet: M-1429 A: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 386: New material, untraced objects, and collections outside India and Pakistan: Suomalainen Tiedeakatemia.
See: Dholavira: Seal: SI. Number: 127: Acc. Number: 25871 (NB. The photograph is of the seal. Therefore, the inscription would be the mirrored image of that seen in the photograph.): R.S. Bisht, 2015: 8.2.3 Details of Individual Seals: Excavations at Dholavira (1989-90 to 2004-2005), p. 288: https://www.scribd.com/document/262316120/Excavations-at-Dholavifra-1989-2005-RS-Bisht-2015: Accessed: 12 November, 2018.
Comment:
The repetition of the word look in text M-1429 A can be likened to the modern Chinese phrase kàn kan 看看, meaning 'take a look at', which you might hear when wandering through a market.
Image Credit:
Indus Script Sign Number 375: Sign List of the Indus Script: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.