[ ɪ'fɛm(ə)rɪs , -'fi:m- ]
■ noun ( plural ephemerides ˌɛfɪ'mɛrɪdi:z ) Astronomy & Astrology a table of the calculated positions of a celestial object at regular intervals throughout a period.
Origin
C16: from L., from Gk ephēmeros 'lasting only a day'.