Is “Aback” a Scrabble word?
Yes
ABACK
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 Aback
/əˈbæk/
adverb
1.Towards the back or rear; backwards.
2.In the rear; a distance behind.
3.By surprise; startled; dumbfounded. (see usage)