κατὰ διάμετρον

kata diametron
Greek · adverb
variant κ δμετρ : k dmetr
Edited by: Thomas Peeters , Kierán Meinhardt
Last edited: 2025-01-29
Meanings
Literal translation
on a diameter
Categories
expression of relative position
astrological concept
aspect
Related Lemmata 8 ›

1. diametrically opposite

1.a diametrically opposite expression of relative position

[...] κ(ατὰ) δ(ιά)μετρ(ον) χρ(όνους) [...] ὡρ(ῶν)

‘... diametrically opposite time-degrees ...’

— P. Oxy. LXI 4142 Fr. 2, 7

Genre: mathematical astronomy: procedure text Provenance: Oxyrhynchus

Jones, A. (ed.), 1999. Astronomical papyri from Oxyrhynchus (P. Oxy. 4133-4300a), Volumes I and II. Philadelphia: American Philosophical Society. II: 28

Ὅταν οὖν κατὰ διάμετρον γένηται ἡ σελήνη τῷ ἡλίῳ, τότε καὶ τὸ σκίασμα τῆς γῆς κατὰ διάμετρον γίνεται τῷ ἡλίῳ· ὅθεν ἡ σελήνη ταπεινοτέρα φερομένη τοῦ σκιάσματος εὐλόγως ἐμπίπτει εἰς τὸ σκίασμα τῆς γῆς.

‘So whenever the Moon becomes diametrically opposite the Sun, the shadow of the Earth too becomes diametrically opposite the Sun; whence the Moon, moving lower than the shadow, logically falls into the shadow of the Earth.’

— Geminus 11.2

Genre: astronomy Date: 1st century BCE

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

2. in opposition

2.a in opposition astrological concept, aspect

Τῆς δὲ πρὸς ἄλληλα τάξεως καὶ θέσεως τῶν ιβʹ ζῳδίων διαφοραί εἰσι τέσσαρες. Ἃ μὲν γὰρ αὐτῶν λέγεται κατὰ διάμετρον, ἃ δὲ κατὰ τρίγωνον, ἃ δὲ κατὰ τετράγωνον, ἃ δὲ κατὰ συζυγίαν, ὑπό τινων δὲ ἀντισυζυγίαν.

‘Of the arrangement in comparison with each other and position of the 12 zodiac signs, there are four distinctions. One of them is called “in opposition”, another one “in trine”, another one “in quartile” and another one “in syzygy”, but according to some “(in) antisyzygy”.’

— Geminus 2.1

Genre: astronomy Date: 1st century BCE

Geminus. 1975. Géminos, Introduction aux Phénomènes, ed. G. Aujac. Paris: Les Belles Lettres. 9-10

Κατὰ διάμετρον μὲν οὖν εἰσι ζῴδια τὰ κατὰ τὴν αὐτὴν διάμετρον κείμενα. Ἔστι δὲ τάδε· Κριὸς Ζυγός, Ταῦρος Σκορπίος, Δίδυμοι Τοξότης, Καρκίνος Αἰγόκερως, Λέων Ὑδροχόος, Παρθένος Ἰχθύες.

‘“In opposition” are the zodiac signs that lie on the same diameter. These are the following: Aries - Libra, Taurus - Scorpio, Gemini - Sagittarius, Cancer - Capricorn, Leo - Aquarius, Virgo - Pisces.’

— Geminus 2.2

Genre: astronomy Date: 1st century BCE

Geminus. 1975. Géminos, Introduction aux Phénomènes, ed. G. Aujac. Paris: Les Belles Lettres. 10

Cite this entry
APA (7th)
Peeters, T., & Meinhardt, K. (2025). κατὰ διάμετρον (Lemma #2678). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/2678/
Chicago (Author-Date)
Peeters, T., & Meinhardt, K. (2025). κατὰ διάμετρον (Lemma #2678). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/2678/
MLA (9th)
Peeters, T., & Meinhardt, K. (2025). κατὰ διάμετρον (Lemma #2678). The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. https://zodiacglossary.github.io/lemma/2678/
Harvard
Peeters, T. and Meinhardt, K. (2025) κατὰ διάμετρον (Lemma #2678), The ZODIAC Glossary: A Cross-Cultural Glossary of Ancient Astral Science. Available at: https://zodiacglossary.github.io/lemma/2678/ (Accessed: July 4, 2026).
BibTeX 
@misc{zodiac2678,
	note = {[Online; accessed 2026-07-04]},
	author = {Peeters, Thomas and Meinhardt, Kierán},
	year = {2025},
	title = {κατὰ διάμετρον ({Lemma} #2678)},
	url = {https://zodiacglossary.github.io/lemma/2678/},
	howpublished = {https://zodiacglossary.github.io/lemma/2678/},
}