What is (a) A circle of latitude or of longitude, as represented on a map. (b) The equator; -- usually called the line, or equinoctial line; as, to cross the line called?

line — (Geog.) (a) A circle of latitude or of longitude, as represented on a map. (b) The equator; -- usually called the line, or equinoctial line; as, to cross the line. (Webster's 1913.)

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