Is “Sigil” a Scrabble word?
Yes
SIGIL
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 Sigil
/ˈsɪdʒəl/
noun
1.A seal, signature or signet.
2.An occult or magical sign, image or symbol.
3.A nonalphanumeric character affixed to a symbol (e.g. variable) to indicate a property such as type or scope.