Is “Boo” a Scrabble word?
Yes
BOO
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 Boo
/buː/
noun
1.A derisive shout made to indicate disapproval.
verb
1.To shout extended boos derisively.
“When he took the podium, the crowd booed.”
2.To shout extended boos at, as a form of derision.
“The protesters loudly booed the visiting senator.”
interjection
1.A loud exclamation intended to scare someone, especially a child. Usually used when one has been hidden from the victim and then suddenly appeared unexpectedly.
2.Used ironically in a situation where one had the opportunity to scare someone by speaking suddenly.
3.An exclamation used by a member or many members of an audience, as at a stage play or sports game, to indicate derision or disapproval of what has just occurred.