noun
Definition: a setting free from the charge of an offense by verdict, sentence, or other legal process
Source: www.merriam-webster.com
This is a legal term that is used often with wrongfully by many, a lawyer, who did not win a case. Also it is not a word that you would be able to understand out of context or sometimes as with many legal files in context without a minor in criminal studies or being a fan of Law and Order.
I had heard this before and from peoples recantations have been able to gauge people reactions and know know what it means fully.