UNCONSCIONABLE
exorbitant, extortionate, outrageous, steep, unconscionable, usurious
(adjective) greatly exceeding bounds of reason or moderation; “exorbitant rent”; “extortionate prices”; “spends an outrageous amount on entertainment”; “usurious interest rate”; “unconscionable spending”
conscienceless, unconscionable
(adjective) lacking a conscience; “a conscienceless villain”; “brash, unprincipled, and conscienceless”; “an unconscionable liar”
Source: WordNet® 3.1
Etymology
Adjective
unconscionable (comparative more unconscionable, superlative most unconscionable)
Not conscionable; unscrupulous and lacking principles or conscience.
Excessive, imprudent or unreasonable.
Source: Wiktionary
Un*con"scion*a*ble, a.
1. Not conscionable; not conforming to reason; unreasonable;
exceeding the limits of any reasonable claim or expectation;
inordinate; as, an unconscionable person or demand; unconscionable
size.
Which use of reason, most reasonless and unconscionable, is the
utmost that any tyrant ever pretended. Milton.
His giantship is gone somewhat crestfallen, Stalking with less
unconscionable strides. Milton.
2. Not guided by, or conformed to, conscience. [Obs.]
Ungenerous as well as unconscionable practices. South.
– Un*con"scion*a*ble*ness, n.
– Un*con"scion*a*bly, adv.
Source: Webster’s Unabridged Dictionary 1913 Edition