Why is αντωνυμία (antonymía) Greek for pronoun?

[Pedroski]

I had expected αντωνυμία (antonymía) to mean antonym, but apparently the word antonym was only coined around 1870.

"an antithetical word," 1867, coined to serve as opposite of synonym, from Greek anti "opposite, against" (see anti-) + onym "name" (from PIE root *no-men- "name"). Perhaps introduced to English in the book "Synonyms and Antonyms" (1867) by the Ven. C.J. Smith, M.A.

What were the Greeks thinking when they made the word αντωνυμία for pronoun?

It seems to be composed of anti- and maybe ognomy? (anti knowledge?? opposite knowledge??)

Thanks in advance for any tips, pointers or ideas!

[billberg23]

1.  Note LSJ s.v. ὄνυμα, ὀνυμάζω, ὀνυμαίνω, ὀνυμαστός, Aeolic and Doric for ὀνομ-. Do you have an LSJ?  If not, download one from the following sites: https://www.google.com/search?q=liddell+scott+jones+greek+english+lexicon+pdf&rlz=1C1CHBF_enUS916US916&oq=Liddell+Scott+Jones&aqs=chrome.3.69i57j0l3j0i22i30.245680j0j4&sourceid=chrome&ie=UTF-8.

2.  The lead vowel of ὀνυμα/ὀνομα ("name," "noun") lengthens from -ο- to -ω- in composition (e.g. ἐπωνυμία, μετωνυμία, etc. etc.), presumably an effect of elision.  Nothing to do with "ognomy."

3.  Regarding ἀντ- in composition, cf. LSJ s.v. ἀντί ("instead of," "in place of") Α ΙΙΙ.

[Pedroski]

Thank you very much!

So it is just: in place of a name, Latin "from pro, here meaning "in place of," + nomen "name, noun" "

I suppose it was just the modern word "antonym" which confused me!

Thanks again!