sidereal day

Noun

 * 1)  One day of sidereal time; the time in which Earth rotates once around its axis, relative to the point of the vernal equinox (about 23 hours, 56 minutes, 4 seconds).
 * 2)  The rotational period of Earth; the time in which Earth rotates around its axis 360 degrees.

Usage notes

 * Although the two above definitions are identical in everyday practice, a sidereal day is normally measured relative to the point of vernal equinox. This, combined with the effect that precession has on the vernal equinox, makes a sidereal day 8 milliseconds shorter than the actual rotational period. However, this difference is small enough that it is usually ignored, so the term is also used for the time of a full 360 degree rotation. When the difference is significant, the term  is used to refer to the time of a full rotation, which is measured relative to the stars.

Translations

 * Chinese:
 * Mandarin:
 * Dutch: siderische dag
 * Finnish: sideerinen vuorokausi
 * French: jour sidéral
 * German: siderischer Tag, Sterntag
 * Japanese: 恒星日
 * Romanian:
 * Russian: звёздные су́тки