Webster's Revised Unabridged Dictionary · 1913

Reasonable

Reasonable (rē"z'n*ȧ*b'l) , adjective

[Old English resonable, French raisonnable, from Latin rationabilis. See Reason, n.]

1.
Having the faculty of reason; endued with reason; rational; as, a reasonable being.
2.
Governed by reason; being under the influence of reason; thinking, speaking or acting rationally, or according to the dictates of reason; agreeable to reason; just; rational; as, the measure must satisfy all reasonable men.
By indubitable certainty, I mean that which doth not admit of any reasonable cause of doubting. — Bp. Wilkins
Men have no right to what is not reasonable. — Burke
3.
Not excessive or immoderate; within due limits; proper; as, a reasonable demand, amount, price.
Let... all things be thought upon That may, with reasonable swiftness, add More feathers to our wings. — Shakespeare

Reasonable , adverb

Reasonably; tolerably. [Obsolete]
I have a reasonable good ear in music. — Shakespeare