Is “Cos” a Scrabble word?
Yes
COS
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 Cos
/kɒs/
noun
1.A variety of lettuce with long, crisp leaves.