This Indus sign is composed of the word obscure, with two light symbols, one at the north-west point and one at the south-east point. In other words, the condition of obscurity is true for the direction north-west to south-east.
Illustrative Text Reference:
Harappa: Pottery Graffiti: H-2549 A: Asko Parpola, B. M. Pande, and Petteri Koskikallio, 2010: Corpus of Indus Seals and Inscriptions: Volume 3,1: Page 351: New material, untraced objects, and collections outside India and Pakistan: Suomalainen Tiedeakatemia.
Comments:
There is only one extant example of this symbol in the Indus inscriptions. The writing was found on a piece of pottery at Harappa, in Trench 11 of Mound E, next to the perimeter wall.
This is an important example of a piece of writing matching the archaeological evidence because the perimeter wall ran from north-west to south-east, at the place where the inscription was found.
Image Credit:
Obscure NW SE: Lynn Fawcett, 2017.