equinoctial
Syllabification: (e·qui·noc·tial)
Pronunciation: /ˌēkwəˈnäkSHəl, ˌekwə-/
Definition of equinoctial
adjective
noun
(also equinoctial line or equinoctial circle)- another term for celestial equator.
Origin:
late Middle English (in the sense 'relating to equal periods of day and night'): via Old French from Latin aequinoctialis, from aequinoctium (see equinox)