The Indus Dictionary Project
This Indus sign has the noun time set inside the noun voice. It is an ideograph for the adverb now or currently.
Mohenjo-daro: Seal: M-1771 a: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 46: New material, untraced objects, and collections outside India and Pakistan: Suomalainen Tiedeakatemia.
I suggest that you think of this ideograph in terms of someone reading from a sundial, and making a public announcement regarding the current time.
Inscription M-1771 refers to a small batch of silk cocoons. Hence, now is used to indicate the need for the consignment to be delivered as quickly as possible.
Indus Script Sign Number 265: Sign List of the Indus Script: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.