This is the symbol for the verb to join with the addition of four legs. It is an ideograph for a domesticated or tame animal. In context, pack animal is normally a good translation.
Illustrative Text Reference:
Mohenjo-daro: Seal: M-1719 a: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 28: New material, untraced objects, and
collections outside India and Pakistan: Suomalainen Tiedeakatemia.
Indus Script Sign Number 2026: List of Sign Variants: Iravatham Mahadevan, 1977: The Indus Script: Texts, Concordance and Tables: The Director General Archaeological Survey of India.