English
rigorous
Rigorous comes from Late Latin rigōrōsus, and goes back to Proto-Indo-European *Hreyǵ-.
- Proto-Indo-Europeanc. 4500–2500 BCE*Hreyǵ-root as named
- Late Latinc. 200–600 CErigōrōsus
- Anglo-Normanc. 1066–1400rigoreus
- Middle Englishc. 1150–1500rigorous
- Englishearliest quotation 1946same form
attested reconstructed ? uncertain or disputed
Lineage
- Proto-Indo-Europeanc. 4500–2500 BCE*Hreyǵ-root as named
- Late Latinc. 200–600 CErigōrōsus
- Anglo-Normanc. 1066–1400rigoreus
- Middle Englishc. 1150–1500rigorous
- Englishearliest quotation 1946same form
Earliest quotation: 1946, and December, George Westinghouse, 1846-1914: “From this time onwards, the Westinghouse air brake literally…”
Equivalent to rigor + -ous
Proto-Italic *rigā- ‘to lead toward’
Latin rigō ‘to be rigid’
Latin rigor ‘stiffness, rigidity, rigor, cold, harshness’
English rigor
Linked words
through Proto-Indo-European *Hreyǵ-
reach, irrigation, rigid, rigour, 8 more
Today it means
adj Showing, causing, or favoring rigour/rigor; scrupulously accurate or strict; thorough.
Language periods are conventional ranges, not dates for this word.
Etymograph / Proto-Indo-European *Hreyǵ- / rigorous