Algol

[Corrupted Arabic.] A fixed star in Medusa's head, in the constellation Perseus. It is called also ẞ Persei. It is technically of 24 magnitude; but really varies in brilliancy from the 2nd to the 4th magnitude in 3 hours, remaining thus for about 20 minutes. In 3 hours more it is again of the 2nd magnitude, at which it continues for 2 days 13 hours, after which the same series of changes takes place again. al-go-log-ic-al, a. [Eng. algolog ( y ); -ical.] Pertaining to algology.