This term is usually used when one does not care about anything... usually very angry and upset. Maybe just an ass hole but give the people who use this word a break because they may just be having a hard time in life.

Noun. A mental device used to measure, usually on a 1-to-10 scale, how much you care or give a fuck. Not useful for articulating high degrees of giving-a-fuck, but perfectly useful for insinuating how little fuck you actually give.

To measure the amount of interest in something based on a personal scale of giving a fuck.