Short but powerful, the word ‘hack’ has multiple lingustic uses. It can be a noun, a verb, an adjective, a verbal phrase and an idiom.
However, I’ve chosen to highlight its use as an adjective.
The word ‘hack’ is a truncation of the word ‘hackneyed,’ which describes something trite and banal.
Example of formal usage:
The lyrics to 13 year-old Rebecca Black’s song, “Friday” are so hackneyed as to be utterly embarrassing.
Example of informal usage:
Jesus H. Christ, they really need to fire the hack writer who wrote that song.