What Does 'Iniquity' Mean?

iniquity [from Latin iniquitas, from inequus unfair, from in- (un-) + aequus (even, level); akin to Mod English equal]
a state of malicious unfairness, inequality, injustice or unrighteousness.
[less commonly] an act of malicious injustice; sin

Its word-field includes wrong(doing), crookedness, and transgression, not leveling with someone, not being 'on the level' with someone. It was often used to translate New Testament Gk adikia, which is injustice as to the law or judges. In Hebrew texts, it was often used to translate Heb. ’awon (bent; stray). Both words are about an action's character rather than the act itself; its sinfulness rather than the sin, its injustice rather than the crime.

The core meaning of 'iniquity' is 'unfair' or 'unjust', but it carries a deeper, more menacing connotation. The word, in older English, usually indicated malice from a depraved or evil or thoroughly selfish state of mind, which is what leads to to being unjust.

I said, 'older English', because 'iniquity' fell out of common use more than a century ago, and when it is used, it is treated merely as a synonym for 'sin'. Bible translators have only recently begun to catch up with the change. 

Iniquity's a perfectly good word to use when you run out of more common ways to describe what it describes, but otherwise it's best to avoid using it outside of literary contexts, unless you just want to sound high and mighty. I would love to see its return in public discussion, regarding the sin of economic injustice and extreme disparity, but until that sort of recovery of the word comes to the general public, the word just sets up a barrier.

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