[ ee-kwuh-nok-shuhl, ek-wuh- ]
See synonyms for equinoctial on Thesaurus.com
  1. pertaining to an equinox or the equinoxes, or to the equality of day and night.

  2. pertaining to the celestial equator.

  1. occurring at or about the time of an equinox.

  2. Botany. (of a flower) opening regularly at a certain hour.

Origin of equinoctial

1350–1400; Middle English <Latin aequinoctiālis pertaining to the equinox. See equinox, -al1

Other words from equinoctial

  • in·ter·e·qui·noc·tial, adjective

Words Nearby equinoctial

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use equinoctial in a sentence

  • Nor is the equinoctial heat more discouraging to them than the accumulated winter of both the poles.

    English: Composition and Literature | W. F. (William Franklin) Webster
  • I don't know if you remember that equinoctial gale that blew about the 18th or 19th.

    My New Curate | P.A. Sheehan
  • She plunged into the chilly equinoctial darkness as the clock struck ten, for her fifteen miles' walk under the steely stars.

  • The next afternoon we crossed the equinoctial line in longitude 21 degrees 50 minutes west.

  • The 'kids' are two little stars which first rise in the evening towards the end of September, during the equinoctial gales.

British Dictionary definitions for equinoctial


/ (ˌiːkwɪˈnɒkʃəl) /

  1. relating to or occurring at either or both equinoxes

  2. (of a plant) having flowers that open and close at specific regular times

  1. astronomy of or relating to the celestial equator

  1. a storm or gale at or near an equinox

  2. another name for celestial equator

Origin of equinoctial

C14: from Latin aequinoctiālis concerning the equinox

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for equinoctial


[ ē′kwə-nŏkshəl, ĕk′wə- ]

  1. Relating to an equinox.

  2. Relating to the celestial equator.


The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.