sidereal day meaning

UK US

sidereal day (noun): the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day.

Definition of sidereal day

  1. the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day

    Synonyms: day

    Type of: time unit, sidereal time

More about sidereal day on Wikipedia.