Synonyms for Reasonable:

adj.

adult (adjective)
full-grown, nubile, mature, adult, developed, virile, serious, of age.
all (adjective)
sensible.
believable (adjective)
credible, plausible, believable.
calm (adjective)
level-headed.
cheap (adjective)
competitive, inexpensive, economical, on sale, budget, reduced, low price, dirt cheap, marked down, half-price, bargain, cheap, at cost.
commonsensical (adjective)
commonsensible.
economical (adjective)
dirt cheap.
intelligent, practical (adjective)
consistent, unprejudiced, cerebral, logical, consequent, levelheaded, credible, conscious, reasoning, wise, commonsensical, tolerant, Perceiving, unbiased, thought-out, ratiocinative, thoughtful, tenable, believable.
moderate, tolerable (adjective)
feasible, impartial, conservative, politic, temperate, rational, prudent, acceptable, discreet, circumspect, modest, judicious, understandable, sane, objective, sensible, inexpensive, right, reflective, fair, humane, analytical, equitable, restrained, sapient, plausible, cheap, legitimate, sound.
reasonable (adjective)
inductive, thinking, likely, sensible, plausible, sound, conceivable, deductive, cogent, intelligent, feasible, rational, thought-out, logical, wise.
sane (adjective)
realistic, Sober-minded, sane, rational, balanced, normal, sensible, well-balanced, right, down-to-earth, lucid.

n.

legitimate, decent, analytical, judicious, impartial, discreet, objective, excessive, humane, natural, right, sapient, accepted, politic, circumspect, prudent, temperate, immoderate, fair-minded, independent, equitable. basic, inclusive, chargeable, all in, extra, understandable, fancy, Discounted, all-inclusive. possible, be able to do something, reason, may, attainable, in principle, viable, humanly possible, practicable, consequent, doable. sage, well-grounded, sagacious. conservative, restrained, restraint, plain. edge, modest, big. money, popular. reasonable (noun)
fairish, fair, commonsense, levelheaded, sound, healthy, commonsensical, sensible, intelligent, sane, moderate, tenable, rational, commonsensible, well-founded, logical.

v.

controlled (verb)
restrained.
moderate (verb)
modest, temperate.

Other synonyms:

equitable, inclusive, accepted, tolerable, well-grounded, possible, respectable, fair-minded, adequate, agreeable, unbiased, satisfactory. analytical, independent, generous, acceptable, all-right, prudent, natural, liberal. discreet, fine, sapient, sage, conservative. sagacious. O.K.. popular. comprehensible
understandable.
logical
consequent, legitimate.
sensible
common sense.
well-advised
judicious.
wise
level-headed.

Usage examples for reasonable

  1. An', lass, it's reasonable – The Mysterious Rider by Zane Grey
  2. " No, no, be reasonable – Sant' Ilario by F. Marion Crawford