The Indus Dictionary Project
In this symbol, the verb to drive is placed over the diagram of a perimeter wall. Hence, it is the noun drivers' area.
Dholavira: Seal: SI. Number: 217: Acc. Number: 51582 (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. 305: https://www.scribd.com/document/262316120/Excavations-at-Dholavifra-1989-2005-RS-Bisht-2015: Accessed: 11 February, 2019.
Mohenjo-daro: Seal: M-1262 a: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 159: Collections in Pakistan: Suomalainen Tiedeakatemia.
Drivers probably had to wait for passengers, their turn in the loading bay, or to pass through border controls. Therefore, this symbol may have referred to the equivalent of the modern day car park or lorry park.
Drivers' Area: Lynn Fawcett, 2019.