Is “Ballcock” a Scrabble word?
Yes
BALLCOCK
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 Ballcock
/ˈbɔːlkɒk/
noun
1.A floating sphere, attached to a lever, that controls the level of liquid in a cistern.