The Indus Dictionary Project
This is a pictograph of a bow with an arrow. Hence, it is the noun weapons, or the adjective armed. In the text on the hollow seal from Ghola Dhoro, this symbol is repeated, giving us the adjective fortified.
Mohenjo-daro: Seal: M-28 a: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 16: Collections in India: Suomalainen Tiedeakatemia.
Gola Dhoro: New find: No CISI number: Hollow seal: Ancient Indus seal found at Gola Dhoro: Photograph [NB. the image has to be flipped in order to resemble a sealing]: © Kuldeep Bhan: https://www.harappa.com/goladhoro/goladhoroseal.html: Accessed: 19 February 2016.
Indus Script Sign Number 307: Sign List of the Indus Script: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.