Is “Yack” a Scrabble word?
Yes
YACK
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 Yack
/jæk/
noun
1.A talk, particular an informal talk; chattering; gossip.
2.A laugh.
3.Vomit.
verb
1.To talk, particularly informally but persistently; to chatter or prattle.
2.To vomit, usually as a result of excessive alcohol consumption.