Is “Blackest” a Scrabble word?
Yes
BLACKEST
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 Blackest
/blækəst/
adjective
1.(of an object) Absorbing all light and reflecting none; dark and hueless.
2.(of a place, etc) Without light.
3.(sometimes capitalized) Of or relating to any of various ethnic groups having dark pigmentation of the skin.
Synonyms: dark, swart, dark, gloomy, pitch-black