This is a pictograph of a silk moth. It is both the singular and plural form of the noun silk moth. Note how the eyes and antennae are the key identifying features for the moth.
Illustrative Text Reference:
Mohenjo-daro: Seal: M-890 a: Sayid Ghulam Mustafa Shah and Asko Parpola, 1991: Corpus of Indus Seals and Inscriptions: Volume 2: Page 84: Collections in Pakistan: Suomalainen Tiedeakatemia.
Image Credit:
Indus Script Sign Number 2117: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.