'Redact' is one of those ugly words (like 'resile') that seems to have insinuated itself into everyday speech without anyone noticing, let alone objecting.
Since 2005, redaction has been used in the public sector to describe the act of obliterating any interesting, sorry I mean 'sensitive', information in response to Freedom of Information requests, usually by use of a black marker pen. It was the publication of MPs' expenses (or rather the publication of Mondrian-esque blocks of black ink) that allowed the word to break out of its status as a piece of public sector jargon, and enter the real world.
The dictionary (Chambers 21st Century) defines 'redact' as 'to edit; to put (text) into the appropriate literary form', and traces its use back to the Latin redigere - to bring back. It is an irony worthy of Orwell that a word associated with tidying up for publication is now used to signify censorship and the suppression of information.