Rodion

Actually, Иродион (Irodion) is the Russian form of Herodion.

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Родион (Rodion) is really the Russian form of Ῥοδίων (Rhodion), which is a Greek short form of the aforementioned Herodion. However, it can also be an independent name on its own, in which case it is derived from the Greek noun ῥόδον (rhodon) meaning "rose".

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The modern Greek form of the name is Ροδίων (Rodion), though the name is rare in modern Greece.

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Sources used:
- the entry for Irodion in the Submitted Names Database and its sources.
- the entry for Rodion at https://heraldry.sca.org/names/paul/r.html (in English)
- http://kurufin.ru/html/Rus_names/rus_r.html (in Russian; scroll down until you see "Herodion" in one of the columns on the right)
- http://kurufin.ru/html/Translate/Rodion.html (in Russian)
- saint Herodion/R(h)odion of Patras (1st century AD): https://en.wikipedia.org/wiki/Herodion_of_Patras (in English; also see the Russian version!)

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- Rodion (1): https://www.trismegistos.org/name/13353 (in English; this is about the name)
- Rodion (2): https://www.trismegistos.org/name/23261 (in English; this is about the name)
- Ῥοδίων (ancient Greek): https://el.wiktionary.org/wiki/Ῥοδίων (in Greek)
- Ροδίων (modern Greek): https://el.wiktionary.org/wiki/Ροδίων (in Greek)
- see the entry for Rhodion at Pavlos' Etymologica: http://web.archive.org/web/20120325073657/http://www.etymologica.com/page22.htm (in English)
- Rhodion at the Lexicon of Greek Personal Names (LGPN): http://clas-lgpn2.classics.ox.ac.uk/cgi-bin/lgpn_search.cgi?namenoaccents=Ροδιων (in English; features 2 results)
- https://glg.csic.es/NombresGriegosDePersona/ListasNombres/NombresDePersona_R.html (in Spanish)
- ῥόδον (rhodon) meaning "rose":
• http://www.perseus.tufts.edu/hopper/morph?l=r%28o%2Fdon&la=greek&can=r%28o%2Fdon (in English)
• https://en.wiktionary.org/wiki/ῥόδον#Ancient_Greek (in English) [noted -ed]