English
radioactive
Radioactive comes from French radio-actif, from actif ‘active’, and ultimately from Proto-Indo-European *h₂eǵ- ‘to drive’.
- Proto-Indo-Europeanc. 4500–2500 BCE*h₂eǵ-‘to drive’reconstructed
- Proto-Indo-European, derivedc. 4500–2500 BCE*h₂éǵeti‘to be driving’reconstructed
- Proto-Italicc. 1500–700 BCE*agō‘to drive’reconstructed
- Latinc. 75 BCE–200 CEago‘to act’
- Latin, derivedc. 75 BCE–200 CEāctīvus‘active’
- Old Frenchc. 842–1400actif‘active’
- Frenchc. 1600–presentactif‘active’
- French, derivedc. 1600–presentradio-actif
- Englishearliest quotation 1917radioactive
attested reconstructed ? uncertain or disputed deepest recorded ancestor
Lineage
- Proto-Indo-Europeanc. 4500–2500 BCE*h₂eǵ-‘to drive’reconstructed
- Proto-Indo-European, derivedc. 4500–2500 BCE*h₂éǵeti‘to be driving’reconstructed
- Proto-Italicc. 1500–700 BCE*agō‘to drive’reconstructed
- Latinc. 75 BCE–200 CEago‘to act’
- Latin, derivedc. 75 BCE–200 CEāctīvus‘active’
- Old Frenchc. 842–1400actif‘active’
- Frenchc. 1600–presentactif‘active’
- French, derivedc. 1600–presentradio-actif
- Englishearliest quotation 1917radioactive
Earliest quotation: 1917, H. G. Wells, The First Vision: “As a matter of fact many of our best…”.
The story
Coined by Pierre Curie and Marie Curie in 1898 as French radio-actif, equivalent to English radio- + active.
Linked words
through Proto-Indo-European *h₂eǵ- ‘to drive’
suggest, register, essay, gesture, acre, digest, congestion, agrarian, belligerent, progesterone, ingest, gestation, agitate, agger, samaj, axiomatic, gerund, gestion, 130 more
through Proto-Indo-European *h₂éǵeti ‘to be driving’
strategy, agony, antagonist, axiom, antagonism, agonist, reactionary, antagonize, glucagon, stratagem, agonize, 103 more
through Proto-Italic *agō ‘to drive’
reaction, transaction, unambiguous, reagent, ambiguously, 81 more
through Latin ago ‘to act’
act, agency, agent, action, actual, actor, agenda, examine, examination, ambiguous, squat, agile, ambiguity, agility, assay, enact, agitation, cogent, actuator, hyperactivity, exigent, inexact, actuation, actuate, redact, 93 more
through Latin āctīvus ‘active’
through Old French actif ‘active’
through French actif ‘active’
Today it means
adj Exhibiting radioactivity.
Language periods are conventional ranges, not dates for this word.
Etymograph / Proto-Indo-European *h₂eǵ- / radioactive