lon·gi·tude (lŏnji-td′, -tyd′, lôn-)
1. Angular distance on the earth's surface, measured east or west from the Prime Meridian at Greenwich, England, to the meridian passing through a position, expressed in degrees (or hours), minutes, and seconds.
2. Celestial longitude.
[Middle English, length, a measured length, fromOld French, fromLatinlongitūdō, longitūdin-, fromlongus, long; see del-1 in the Appendix of Indo-European roots.]
(click for a larger image)longitude
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