Definition of longitude
1a
: angular distance measured on a great circle of reference from the intersection of the adopted zero meridian with this reference circle to the similar intersection of the meridian passing through the object
b
: the arc or portion of the earth's equator intersected between the meridian of a given place and the prime meridian and expressed either in degrees or in time
2
archaic
: long duration
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Merriam-Webster unabridged
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Time Traveler for longitude
The first known use of longitude was in the 15th century
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