As adjectives the difference between iniquitous and unmentionable
is that iniquitous is wicked or sinful while unmentionable is not mentionable.
iniquitous
English
Adjective
(
en adjective)
wicked or sinful
morally objectionable
Synonyms
* (wicked :) flagitious
* (wicked :) nefarious
* (morally objectionable :) perverse
Antonyms
* (wicked :) righteous
* (morally objectionable :) righteous
unmentionable
English
Derived terms
* unmentionables
* unmentionably