The Indus Dictionary Project
This pictograph of an adult person has two distinguishing features. Firstly, there is a length of fabric around his waist. In other words, a sash. The sash tells us that he is a person of authority. Secondly, he is wearing footwear with turned up toes. This tells us that he comes from outside of the region.
It is therefore possible to conclude that Mahadevan's sign number 2630 is the noun foreign official.
Mohenjo-daro: Seal: M-142 a: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 45: Collections in India: Suomalainen Tiedeakatemia.
Footwear with turned up toes has been in and out of fashion in various places for millennia. A good example (of boots with turned up toes) can be seen on the Met Museum website¹. However, the fact that there is only a small group of Indus symbols wearing such footwear, suggests that the official depicted was foreign.
The length of the waist sash may indicate the official's rank.
Indus Script Sign Number 2630: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.
1. A Proto-Elamite figure wears boots with turned up toes: The Metropolitan Museum of Art: Accession Number: 2007.280: https://www.metmuseum.org/toah/works-of-art/2007.280/: Accessed: 15 March 2018.