ἰσημερινὸς κύκλος
isēmerinos kuklos

Greek noun

Last edited: 2025-03-25
Primary meaning celestial equator
Literal translation equinoctial circle
Variants
ἰσημερινὸς κύκλος isēmerinos kuklos
κύκλος ἰσημερινός kuklos isēmerinos
Edited by
celestial equator astral concept

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

Παράλληλοι μὲν οἱ τοὺς αὐτοὺς πόλους ἔχοντες τῷ κόσμῳ. Εἰσί δὲ παράλληλοι κύκλοι εʹ· ἀρκτικός, θερινὸς τροπικός, ἰσημερινός, χειμερινὸς τροπικός, ἀνταρκτικός.

‘Parallel are those that have the same poles as the cosmos. There are 5 parallel circles: the arctic circle, the summer tropic, the celestial equator, the winter tropic, the antarctic circle.’

— Geminus 5.1

Genre: astronomy
Date: 1st century BCE

Geminus. 1975. Géminos, Introduction aux Phénomènes, ed. G. Aujac. Paris: Les Belles Lettres. 21

Cite this entry
APA (7th)
Peeters, T. (2025). ἰσημερινὸς κύκλος (Lemma #1279). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1279/
Chicago (Author-Date)
Peeters, T. (2025). ἰσημερινὸς κύκλος (Lemma #1279). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1279/
MLA (9th)
Peeters, T. (2025). ἰσημερινὸς κύκλος (Lemma #1279). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/1279/
Harvard
Peeters, T. (2025) ἰσημερινὸς κύκλος (Lemma #1279), The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. Available at: https://zodiacglossary.github.io/lemma/1279/ (Accessed: December 1, 2025).
BibTeX 
@misc{zodiac1279,
	note = {[Online; accessed 2025-12-01]},
	author = {Peeters, Thomas},
	year = {2025},
	title = {ἰσημερινὸς κύκλος ({Lemma} #1279)},
	url = {https://zodiacglossary.github.io/lemma/1279/},
	howpublished = {https://zodiacglossary.github.io/lemma/1279/},
}