πλάγιος

Forms

πλάγῐος (plágios) m (feminine πλᾰγίᾱ, neuter πλάγῐον); first/second declension^[1]

Etymology

Wiktionary derives it from Ancient Greek πλάγος (plágos, “side”) + -ιος (-ios).^[1] Beekes notes that a reconstruction Proto-Indo-European *pl̥g-iHo- clashes with a cognate such as πέλαγος (pélagos, “sea”), which needs a root with a laryngeal.^[2] Germanic words such as Old High German flah (“flat”) and Old Saxon flaka (“sole of the foot”) point to *plag-.^[2] Since Proto-Indo-European had no phoneme /a/, Beekes suggests the word may come from a European substrate, like πλάξ (pláx, “flat surface”).^[2] He also reports Van Beek's suggestion of a link with πλάζω (plázō, “to lead astray”), which fits the meaning better.^[2] The CGL also connects it with πλάζω (plázō).^[2][3]

Chantraine instead derives it from a noun with the stem πλαγ- (plag-), from Proto-Indo-European *pl̥h₂-g-, with Latin plaga (“expanse; hunting net”), and the long-vowel form in Old Norse flóki (“flounder”); he traces the whole group, παλάμη (palámē, “palm”) included, to a root *pelh₂-.^[4]

Earliest recorded meaning

Beekes dates it from Pindar and Ionic-Attic, meaning oblique, athwart or sloping; the neuter plural meant the sides or flanks.^[2] The earliest texts in the GLAUx corpus are Pindar's Nemean and Isthmian odes.^[5]

Semantic evolution

In classical prose it describes things set sideways: Thucydides uses it of ships moored broadside across a harbour mouth, Plato of transverse motion as opposed to straight ahead, Xenophon of a cutting planted horizontally.^[3][6] Beekes holds that the sense “horizontal”, which Frisk puts first, came from “transverse”.^[2] As a military word it meant on the flank, and the neuter plural meant slopes, sides or borders.^[3] Geometers used it for the transverse diameter of a conic section.^[6] The Septuagint has the derivative πλαγιάζω (plagiázō, “to turn aside, lead astray”).^[2]

The adjective continued in medieval Greek and survives in Modern Greek πλάγιος (plágios), a learned word whose senses “oblique” and “collateral” were modelled on French oblique and collatéraux.^[7][8]

Timeline

• 6th–5th century BC – Pindar uses it.^[2][5][9]
• 5th century BC – Thucydides uses it of ships placed broadside.^[3][6][9]
• 5th–4th century BC – Plato uses it of oblique motion, Xenophon of troops on the flank.^[3][6][9]
• 3rd–2nd century BC – Apollonius of Perga uses it for the transverse diameter.^[6][9]
• Modern Greek – It survives as a learned word, Modern Greek πλάγιος (plágios), with senses calqued on French.^[8]

Meanings

Adjective

1. Placed or moving sideways; oblique, transverse, athwart.^[3][6]
2. (military) On the flank.^[3]
3. (neuter as noun) A slope; in the plural, the sides or borders of a place.^[3][2]
4. (geometry) Transverse, of the diameter of a conic section.^[6]
5. Crooked.^[2]

Word family

• πλαγιάζω (plagiázō)
• πλαγίαυλος (plagíaulos)
• παραπλάγιος (paraplágios)
• πλαγιόω (plagióō)

Related words

• πλάξ (pláx)
• πλάζω (plázō)
• πέλαγος (pélagos)

References

1. ^ a b c d e Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k Beekes, Robert S. P. (2010), Etymological Dictionary of Greek, with the assistance of Lucien van Beek, Leiden Indo-European Etymological Dictionary Series 10, Leiden; Boston: Brill
3. ^ a b c d e f g h Diggle, James, et al., eds. (2021), The Cambridge Greek Lexicon, Cambridge: Cambridge University Press
4. ^ Chantraine, Pierre (2009), Dictionnaire étymologique de la langue grecque: histoire des mots, new ed. with a supplement (Chroniques d'étymologie grecque 1–10), Paris: Klincksieck
5. ^ a b Keersmaekers, Alek (2021–2025), GLAUx: The Greek Language Automated corpus, https://github.com/alekkeersmaekers/glaux
6. ^ a b c d e f g Liddell, Henry George; Scott, Robert; Jones, Henry Stuart (1940), A Greek-English Lexicon, 9th ed., Oxford: Clarendon Press
7. ^ Kriaras, Emmanuel, Επιτομή του Λεξικού της μεσαιωνικής ελληνικής δημώδους γραμματείας 1100–1669, Κέντρο Ελληνικής Γλώσσας, https://www.greek-language.gr
8. ^ a b Ινστιτούτο Νεοελληνικών Σπουδών (Ίδρυμα Μανόλη Τριανταφυλλίδη) (1998), Λεξικό της κοινής νεοελληνικής, Thessaloniki: Aristotle University of Thessaloniki
9. ^ a b c d Rodríguez Adrados, Francisco, et al., eds. (1980–), Diccionario Griego-Español, Madrid: CSIC, http://dge.cchs.csic.es/xdge