Synonyms for Unconscionable (same or very similar meaning)
WordNet sense 1 (lacking a conscience):
conscienceless
WordNet sense 2 (not conscientious; not guided by a sense of right and wrong):
unconscientious
WordNet sense 3 (greatly exceeding bounds of reason or moderation):
exorbitant, extortionate, outrageous, steep, usurious
WordNet sense 4 (not within reasonable limits):
immoderate
From the ODE community, based on WordNet
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