Al·gol (ălgŏl′, -gôl′)
A binary, eclipsing variable star in the constellation Perseus, almost as bright as Polaris.
[Arabic (ra's) al-ġūl, (head) of the ghoul : al-, the + ġūl, ghoul (so called because the star was considered to represent the head of Medusa held by Perseus); see ġwl in the Appendix of Semitic roots.]
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