No, raw is absolutely not a file format. It merely describes the file format, which is simply the common word describing the unchanged state of the file or capture, or yes, even uncooked meat in your example. CR2 or NEF (Canon and Nikon, respectively), for example, are the file formats for the raw capture, which are acronyms.
Since we're in this thread, I think it's reasonable to point out that CR2 certainly isn't an acronym: how on earth would you pronounce it? It's an abbreviation (Canon Raw v2?).
NEF is an acronym, standing for Nikon Electronic File (I think).