# ἰός
## Ancient Greek
### Etymology 1

From Proto-Hellenic *ihwós, a thematicization of Proto-Indo-European *(H)isu- (“arrow”). Cognates include Sanskrit इषु (íṣu, “arrow”) and Avestan 𐬌𐬱𐬎 (išu, “arrow”).

#### Pronunciation

* IPA: /iː.ós/ → /iˈos/ → /iˈos/
* (5th BCE Attic) IPA: /iː.ós/
* (1st CE Egyptian) IPA: /iˈos/
* (4th CE Koine) IPA: /iˈos/
* (10th CE Byzantine) IPA: /iˈos/
* (15th CE Constantinopolitan) IPA: /iˈos/

#### Noun

ῑ̓ός • (īós) m (genitive ῑ̓οῦ); second declension
* arrow
** 800 BCE – 600 BCE, Homer, Iliad 1.48:ἕζετ’ ἔπειτ’ ἀπάνευθε νεῶν, μετὰ δ’ ἰὸν ἕηκεhézet’ épeit’ apáneuthe neôn, metà d’ iòn héēkeThen he sat down apart from the ships and let fly an arrow.

##### Inflection

Heteroclitic neuter plural:

##### Derived terms

* ἰαφέτης (iaphétēs)
* ἰοβόλος (iobólos)
* ἰοδόκος (iodókos)
* ἰοτυπής (iotupḗs)
* ἰοχέαιρα (iokhéaira)

### Etymology 2

From Proto-Hellenic *wihós, from Proto-Indo-European *wisós (“fluidity, slime, poison”). Cognates include Sanskrit विष (víṣa), Latin vīrus, Tocharian A wäs, Tocharian B wase, and Middle Irish fí.

#### Pronunciation

* IPA: /iː.ós/ → /iˈos/ → /iˈos/
* (5th BCE Attic) IPA: /iː.ós/
* (1st CE Egyptian) IPA: /iˈos/
* (4th CE Koine) IPA: /iˈos/
* (10th CE Byzantine) IPA: /iˈos/
* (15th CE Constantinopolitan) IPA: /iˈos/

#### Noun

ῑ̓ός • (īós) m (genitive ῑ̓οῦ); second declension
* poison, venom
** :καὶ μὴ τυχοῦσαι πράγματος νικηφόρου, χώρᾳ μεταῦθις ἰὸς ἐκ φρονημάτων πέδοι πεσὼν ἄφερτος αἰανὴς νόσοςkaì mḕ tukhoûsai prágmatos nikēphórou, khṓrāi metaûthis iòs ek phronēmátōn pédoi pesṑn áphertos aianḕs nósosAnd if they fail to win their cause, the venom from their resentment will fall upon the ground, an intolerable, perpetual plague afterwards in the land.

##### Derived terms

* ἰοβόλος (iobólos)
* ἰοβόρος (iobóros)
* ἰοδόκος (iodókos)
* ἰοειδής (ioeidḗs)
* ἰόεις (ióeis)
* ἰολόχευτος (iolókheutos)
* ἰομιγής (iomigḗs)
* ἰοτόκος (iotókos)
* ἰοφόρος (iophóros)
* ἰώδης (iṓdēs)

##### Descendants

* Greek: ιός m (iós, “venom”)

### Etymology 3

Uncertain. May be of the same origin as Etymology 2.

#### Pronunciation

* IPA: /iː.ós/ → /iˈos/ → /iˈos/
* (5th BCE Attic) IPA: /iː.ós/
* (1st CE Egyptian) IPA: /iˈos/
* (4th CE Koine) IPA: /iˈos/
* (10th CE Byzantine) IPA: /iˈos/
* (15th CE Constantinopolitan) IPA: /iˈos/

#### Noun

ῑ̓ός • (īós) m (genitive ῑ̓οῦ); second declension
* rust, verdigris
** 380 BCE, Plato, The Republic 609a:κακὸν ἑκάστῳ τι καὶ ἀγαθὸν λέγεις; οῖον ὀφθαλμοῖς ὀφθαλμίαν […] χαλκῷ δὲ καὶ σιδήρῳ ἰόνkakòn hekástōi ti kaì agathòn légeis? oîon ophthalmoîs ophthalmían […] khalkôi dè kaì sidḗrōi iónDo you say that there is for everything its special good and evil, as for the eyes ophthalmia […] and for bronze and iron rust?

##### Derived terms

* ἰάζω (iázō)
* ἰίζω (iízō)
* ἰόομαι (ióomai)
* ἰοποίησις (iopoíēsis)
* ἰώδης (iṓdēs)

### Etymology 4

Expansion of original feminine-only pronoun ἴᾱ (íā), from *(h₁)éy.

#### Pronunciation

* IPA: /i.ós/ → /iˈos/ → /iˈos/
* (5th BCE Attic) IPA: /i.ós/
* (1st CE Egyptian) IPA: /iˈos/
* (4th CE Koine) IPA: /iˈos/
* (10th CE Byzantine) IPA: /iˈos/
* (15th CE Constantinopolitan) IPA: /iˈos/

#### Adjective

ῐός • (ĭós) m (feminine ῐ̓́ᾰ, neuter ῐ̓όν); first/second declension
* selfsame; identical

##### Inflection
### References

* ↑ Beekes, Robert S. P. (2010) “ῑ̓ός 2”, in Etymological Dictionary of Greek (Leiden Indo-European Etymological Dictionary Series; 10), volume I, with the assistance of Lucien van Beek, Leiden, Boston: Brill, →ISBN, page 595
* ↑ Beekes, Robert S. P. (2010) “ῑ̓ός 3”, in Etymological Dictionary of Greek (Leiden Indo-European Etymological Dictionary Series; 10), volume I, with the assistance of Lucien van Beek, Leiden, Boston: Brill, →ISBN, page 595
* ↑ Beekes, Robert S. P. (2010) “ῑ̓ός 4”, in Etymological Dictionary of Greek (Leiden Indo-European Etymological Dictionary Series; 10), volume I, with the assistance of Lucien van Beek, Leiden, Boston: Brill, →ISBN, page 595
* ↑ Beekes, Robert S. P. (2010) “ἴα”, in Etymological Dictionary of Greek (Leiden Indo-European Etymological Dictionary Series; 10), volume I, with the assistance of Lucien van Beek, Leiden, Boston: Brill, →ISBN, page 571

### Further reading

* “ἰός”, in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
* “ἰός”, in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
* “ἰός”, in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
* “ἰός”, in Liddell & Scott (1940) A Greek–English Lexicon, Oxford: Clarendon Press
* “ἰός”, in Liddell & Scott (1889) An Intermediate Greek–English Lexicon, New York: Harper & Brothers
* “ἰός”, in Autenrieth, Georg (1891) A Homeric Dictionary for Schools and Colleges, New York: Harper and Brothers
* ἰός in Bailly, Anatole (1935) Le Grand Bailly: Dictionnaire grec-français, Paris: Hachette
* Bauer, Walter et al. (2001) A Greek–English Lexicon of the New Testament and Other Early Christian Literature, Third edition, Chicago: University of Chicago Press
* ἰός in Cunliffe, Richard J. (1924) A Lexicon of the Homeric Dialect: Expanded Edition, Norman: University of Oklahoma Press, published 1963
* “ἰός”, in Slater, William J. (1969) Lexicon to Pindar, Berlin: Walter de Gruyter
* G2447 in Strong, James (1979) Strong’s Exhaustive Concordance to the Bible
* Woodhouse, S. C. (1910) English–Greek Dictionary: A Vocabulary of the Attic Language‎, London: Routledge & Kegan Paul Limited. arrow idem, page 42.bane idem, page 61.bolt idem, page 88.decay idem, page 199.poison idem, page 624.rot idem, page 721.rust idem, page 728.shaft idem, page 760.venom idem, page 947.