Is “Grumpiest” a Scrabble word?
Yes
GRUMPIEST
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 Grumpiest
adjective
1.Dissatisfied and irritable.
“The old man was grumpy because he couldn’t find his glasses.”
Synonyms: cantankerous, crabby, cranky, grouchy, surly, truculent