The Indus Dictionary Project
This is a pictograph of a drinking horn. Hence, it is the noun drinking horn.
Mohenjo-daro: Seal: M-402 a: Jagat Pati Joshi and Asko Parpola, 1987: Corpus of Indus Seals and Inscriptions: Volume 1: Page 97: Collections in India: Suomalainen Tiedeakatemia.
Although lines drawn across an object normally indicate the object's size, the position of the lines on this drinking horn appear to depict some kind of grip.
Drinking Horn: Lynn Fawcett, 2018.