This is a pictograph of a cocoon with the addition of a pattern depicting a braided cord. Hence, it is an ideograph for the noun cord.
Illustrative Text Reference:
Mohenjo-daro: Seal: M-1739 a: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 37: New material, untraced objects, and collections outside India and Pakistan: Suomalainen Tiedeakatemia.
Comment:
In inscription M-1739, the noun cord is followed by the verb to split. It means to unleash or release. It was used in the context of a yak caravan, wherein the animals travel in herd formation rather than in a roped line.
For image credits, please see below.
Image Credits:
Indus Script Sign Numbers 412 and 1100: Sign List of the Indus Script and List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.