From The Collaborative International Dictionary of English v.0.48 [gcide]:
Unreasonable \Un*rea"son*a*ble\, a.
Not reasonable; irrational; immoderate; exorbitant. --
Un*rea"son*a*ble*ness, n. -- Un*rea"son*a*bly, adv.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
unreasonably
adv 1: not in a reasonable or intelligent manner; "she reacted
unreasonably when she learned she had failed" [ant:
reasonably, sanely, sensibly]
2: to a degree that exceeds the bounds or reason or moderation;
"his prices are unreasonably high" [syn: unreasonably,
immoderately] [ant: fairly, jolly, middling,
moderately, passably, pretty, reasonably, somewhat]