Though square, they roll (4)
I believe the answer is:
dice
'though square' is the definition.
'dice' can be an answer for 'square' (thesaurus). I'm not sure about the 'though' bit.
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for dice that I've seen before include "Numbered cube(s)" , "Gambling pieces" , "Random number generators" , "Make into chips" , "Gambling items" .)