Answer:

GNOMON

AnswerCrossword Clue
GNOMONSundial pointer
GNOMONSundial's shadow-caster
GNOMONSundial's shadow caster
GNOMONSundial shadow-caster
GNOMONPin of a sundial.
GNOMONPart of a sundial.
GNOMONSundial style
GNOMONEarly astronomical instrument
GNOMONPart of a sundial that casts a shadow
GNOMONSundial's essential part
GNOMONSundial part