σύμμετρος

Forms

σύμμετρος (súmmetros) m or f (neuter σύμμετρον); second declension^[1] Older Attic ξύμμετρος (xúmmetros), in Aeschylus and Sophocles.^[2][3]

Etymology

It is formed from Ancient Greek συν- (sun-, “with”) + μέτρον (métron, “measure”), with the adjective ending -ος (-os): “having the same measure”.^[1][2][3]

Earliest recorded meaning

It is first found in Aeschylus's Libation Bearers, where a lock of hair is compared to a head it matches, and a firebrand is said to last as long as a life.^[2][3]

Semantic evolution

In tragedy it is used of things of equal size or duration: Sophocles calls a man “of like age” with another, and uses it of an arrival that is well timed and of someone within hearing distance, and Euripides has it of a footprint matching a foot.^[2][3]

In Plato and Aristotle it became a term of mathematics: lines that can be measured by the same unit are “commensurable”, and Aristotle repeatedly says that the diagonal of a square is not commensurable with its side; in the Nicomachean Ethics money makes all things commensurable.^[2][3] The same authors use it for what is in due proportion, set against excess and deficiency, and Plato joins “the well-proportioned and the beautiful”.^[2][3] In prose from Isocrates on it also means suitable, adequate or moderate, of words of praise, exercise, food and resources.^[2][3] Sophocles' elegy and Timotheus use it of what fits the metre or keeps time.^[2][3]

Modern Greek uses it as a learned word, σύμμετρος (símetros), for what keeps a proportion between its parts, and in mathematics for magnitudes with a common measure.^[4]

Timeline

• 6th–5th century BC – Aeschylus uses it of a lock of hair matching a head and of a firebrand lasting as long as a life.^[2][3]
• 5th century BC – Sophocles uses it of a man of like age and of a well-timed arrival.^[2][3]
• 5th–4th century BC – Plato uses it in mathematics for lines with a common measure, and for what is in due proportion.^[2][3]
• 4th century BC – Aristotle denies that the diagonal of a square is commensurable with its side.^[2]
• 2nd century AD – Ptolemy's Harmonics uses the comparative of musical intervals.^[2]
• Modern Greek – The learned σύμμετρος (símetros) means proportional, and in mathematics commensurable.^[4]

Meanings

Adjective

1. Of the same measure or size as something, matching, with a dative.^[2][3]
2. Of equal duration; of like age; coinciding in time, well timed.^[2][3]
3. (mathematics) Having a common measure, commensurable.^[2][3]
4. In accord with the metre; keeping time.^[2][3]
5. Proportionate, suitable or adequate to something.^[2][3]
6. In due proportion, well-proportioned, symmetrical.^[2][3]
7. Of moderate size or amount, moderate.^[2][3]
8. At a suitable distance, within range (for hearing).^[2][3]

Related words

• συμμετρία (summetría)
• μέτρον (métron)
• ἀσύμμετρος (asúmmetros)

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t u Liddell, Henry George; Scott, Robert; Jones, Henry Stuart (1940), A Greek-English Lexicon, 9th ed., Oxford: Clarendon Press
3. ^ a b c d e f g h i j k l m n o p q r s Diggle, James, et al., eds. (2021), The Cambridge Greek Lexicon, Cambridge: Cambridge University Press
4. ^ a b Ινστιτούτο Νεοελληνικών Σπουδών (Ίδρυμα Μανόλη Τριανταφυλλίδη) (1998), Λεξικό της κοινής νεοελληνικής, Thessaloniki: Aristotle University of Thessaloniki