Is “Frustum” a Scrabble word?
Yes
FRUSTUM
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 Frustum
noun
1.A cone or pyramid whose tip has been truncated by a plane parallel to its base.
2.A portion of a sphere, or in general any solid, delimited by two parallel planes.