Is “Shiur” a Scrabble word?
Yes
SHIUR
Valid in at least one Scrabble dictionary
Valid in these dictionaries
SOWPODS / CSW
Scrabble UK & International
TWL / NWL
Scrabble North America
Large English Dictionary
General English word list
Meaning of Shiur
/ʃiˈuːɹ/
noun
1.A lesson on a topic in the Torah.