φθινοπωρινὴ ἰσημερία

phthinopōrinē isēmeria
Greek · noun
variant ἰσημερία φθινοπωρινὴ : isēmeria phthinopōrinē
Edited by: Thomas Peeters
Last edited: 2026-10-23
Meanings
Literal translation
autumnal equinox
Categories
annual phenomenon
Related Lemmata 4 ›

1. autumnal equinox

1.a autumnal equinox annual phenomenon

Ἰσημερία δέ ἐστι φθινοπωρινή, ὅταν ὁ ἥλιος ἀπ’ ἄρκτων πρὸς μεσημβρίαν παροδεύων πάλιν ἐπὶ τοῦ ἰσημερινοῦ γένηται κύκλου καὶ ἴσην τὴν ἡμέραν τῇ νυκτερινῇ ποιήσηται.

‘And it is autumnal equinox, when the sun, in passing from north to south, arrives at the celestial equator again and makes the day equal to the night.’

— Geminus 1.11

Genre: astronomy Date: 1st century BCE

Geminus. 1975. Géminos, Introduction aux Phénomènes, ed. G. Aujac. Paris: Les Belles Lettres. 4

Cite this entry
APA (7th)
Peeters, T. (2026). φθινοπωρινὴ ἰσημερία (Lemma #1273). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1273/
Chicago (Author-Date)
Peeters, T. (2026). φθινοπωρινὴ ἰσημερία (Lemma #1273). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1273/
MLA (9th)
Peeters, T. (2026). φθινοπωρινὴ ἰσημερία (Lemma #1273). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1273/
Harvard
Peeters, T. (2026) φθινοπωρινὴ ἰσημερία (Lemma #1273), The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. Available at: https://zodiacglossary.github.io/lemma/1273/ (Accessed: November 5, 2026).
BibTeX 
@misc{zodiac1273,
	note = {[Online; accessed 2026-11-05]},
	author = {Peeters, Thomas},
	year = {2026},
	title = {φθινοπωρινὴ ἰσημερία ({Lemma} #1273)},
	url = {https://zodiacglossary.github.io/lemma/1273/},
	howpublished = {https://zodiacglossary.github.io/lemma/1273/},
}