# sidereal time

> English word · Noun · IPA /saɪˈdɪə.riəl taɪm/

## Definitions
1. Time measured by the apparent diurnal motion of the vernal equinox; approximated by that based on the rotation of planet Earth relative to the seemingly fixed stars.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/sidereal-time