1250–1300; Middle English resonable
< Middle French raisonnable
< Latin ratiōnābilis.
reasonableness, reasonability, nounreasonably, adverbhalf-reasonable, adjectivehalf-reasonably, adverbnonreasonability, nounnonreasonable, adjectivenonreasonableness, nounnonreasonably, adverbquasi-reasonable, adjectivequasi-reasonably, adverb
Can be confused
(see synonym study at the current entry)
intelligent, judicious, wise, equitable. Reasonable, rational
refer to the faculty of reasoning. Rational
can refer to the reasoning faculty itself or to something derived from that faculty: rational powers; a rational analysis.
It can also mean sane or sensible: She was no longer rational; a rational plan. Reasonable
most often means sensible: A reasonable supposition is one which appeals to our common sense. 2.
equitable, fair, just. See moderate