English
radiant
Radiant comes from Latin radiāns ‘shining, beaming’, from radiō ‘to emit rays or beams’, and perhaps ultimately from Proto-Indo-European *neredʰ- ‘extend forth, rise, outward’.
- Proto-Indo-Europeanc. 4500–2500 BCE*neredʰ-1‘extend forth, rise, outward’uncertain
- Latinc. 75 BCE–200 CEradius2‘spoke of a wheel’
- Latinc. 75 BCE–200 CEradiō3as radiāre, present participle‘to emit rays or beams’
- Latinc. 75 BCE–200 CEradiāns3‘shining, beaming’
- Middle Englishc. 1150–1500radyant3
- Englishearliest quotation 1791radiant3
attested reconstructed ? uncertain or disputed deepest recorded ancestor
- 1 Wiktionary, Latin radius
- 2 Wiktionary, Latin radio
- 3 Wiktionary, English radiant
- Earliest quotation in Wiktionary’s entry: 1791, Homer, [The Iliad.] Book III.: “They in ranks / Sat all, where ſtood the…”.
Lineage
- Proto-Indo-Europeanc. 4500–2500 BCE*neredʰ-Wiktionary, Latin radius‘extend forth, rise, outward’uncertain
- Latinc. 75 BCE–200 CEradiusWiktionary, Latin radio‘spoke of a wheel’
- Latinc. 75 BCE–200 CEradiōWiktionary, English radiantas radiāre, present participle‘to emit rays or beams’
- Latinc. 75 BCE–200 CEradiānsWiktionary, English radiant‘shining, beaming’
- Middle Englishc. 1150–1500radyantWiktionary, English radiant
- Englishearliest quotation 1791radiantWiktionary, English radiant. Earliest quotation in Wiktionary’s entry: 1791, Homer, [The Iliad.] Book III.: “They in ranks / Sat all, where ſtood the…”
Linked words
through Latin radius ‘spoke of a wheel’
through Latin radiō ‘to emit rays or beams’
Today it means
adj Radiating light and/or heat.
Sources
Sources: Wiktionary, “radiant”; the older steps come from the Wiktionary entries for Latin radius, Latin radio. By Wiktionary contributors, CC BY-SA 4.0, via kaikki.org (dump of Oct 3 2026); text adapted and restructured. Language periods are conventional ranges, not dates for this word. License.
Etymograph / Proto-Indo-European *neredʰ- / radiant