noun · 2 senses · updated from the 2026-07-25 local source snapshot
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
Sound
Pronunciation
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/saɪˈdɪə.ɹiəl taɪm/
/səɪˈdɪə.ɹiəl taɪm/
1
noun
Meaning 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.
Definition source: English Wiktionary via Wiktextract
Usage: uncountable
Topics: astronomy, natural-sciences
No example sentence was provided for this meaning.
Meaning relationships
Synonyms: none provided
Antonyms: none provided
2
noun
Meaning 2
measured by the diurnal motion of stars
Definition source: Princeton WordNet 3.0
No example sentence was provided for this meaning.