Is “Showstopper” a Scrabble word?
Yes
SHOWSTOPPER
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 Showstopper
noun
1.A performance or segment of a theatrical production that induces a positive audience reaction strong enough to pause the production.
2.Any impediment that prevents all further progress; especially a software bug that must be fixed before any further development is possible.