The Indus Dictionary Project
Mahadevan's sign number 284 has two possible readings, each of which gives us the noun city.
Firstly, there are four structures, which can be read as a pictograph of buildings interspersed with roads. The buildings are located inside a perimeter wall.
Secondly, there is an ideograph of four voices inside a perimeter wall. In Chinese, four voices is the character jí 㗊, meaning a clamour.
Harappa: Seal: H-143 a: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 200: Collections in India: Suomalainen Tiedeakatemia.
Indus Script Sign Number 284: Sign List of the Indus Script: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.