The Indus Dictionary Project
This is a pictograph of a stepped shrine with five storeys. Hence, it is the noun shrine.
Harappa: Tablet: H-187 A: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 210: Collections in India: Suomalainen Tiedeakatemia.
It is interesting that the motif on side B of tablet H-187 depicts a tree. The tree may be cedrus deodara.
Indus Script Sign Number 1066: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.