Webster's 1828 Dictionary
PERISCIAN
n.[Gr. around, and shadow. ] An inhabitant of a frigid zone or within a polar circle, whose shadow moves round, and in the course of the day falls in every point of compass. The Greek word periscii, in the plural, is generally used in geographies; but the English word is preferable.
Webster's 1913 Dictionary
PERISCIAN
Pe *ris "cian, a. Etym: [Gr. périscien.]
Defn: Having the shadow moving all around.
PERISCIANS; PERISCII
Pe *ris "cians, Pe *ris "ci *i, n. pl. Etym: [NL. See Periscian. ]
Defn: Those who live within a polar circle, whose shadows, during some summer days, will move entirely round, falling toward every point of the compass.
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