nounWord forms: plural ˌepheˈmeriˌdes (ˌɛfəˈmɛrəˌdiz
1. a table giving the computed positions of a celestial body for every day of a given period
2. an astronomical almanac containing such tables
Webster’s New World College Dictionary, Fourth Edition, compiled by the
editors of Webster’s New World Dictionaries. Copyright © 2010 by Houghton
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