Where does “rational” come from?

Rational comes from Old French rationel, from Latin rationalis, derived from Latin ratio (reckoning, reason) and the Latin adjective suffix -alis, ultimately from Proto-Indo-European h₂reh₁- (to count, reckon).

rational (English): Capable of reasoning; Logically sound; not...

Definitions

  1. Capable of reasoning; Logically sound; not...

Ancestry of “rational”, step by step

rational traces back through two separate lines of ancestry.

via French rationalité

StepLanguageWordMeaning
1Frenchrationalitérationality
2Frenchrationnelrational
3Latinrationalisaccounts; rational, reasonable, of or possessing...
4Latinratiōreason, reasoning, explanation, ground, motive, rationality, rationale, purpose
5Latin-tiōtion, -ation, -ing
6Latindissertātiō(spoken) dissertation, discourse, disquisition
7Latindissertusarranged, disposed; explained
8Latindissereresecond-person singular future passive indicative...
9Latindis-asunder, apart, in two; reversal, removal;...
10Latincalceusshoe
11Latincalxlimestone; chalk; the finish line
12Ancient Greekχάλιξsmall stone, pebble; gravel, rubble

via Old French rational

StepLanguageWordMeaning
1Old Frenchrational

Words derived from “rational

Every word from Ancient Greek χάλιξ