“Meat as defined by the CFR, is the muscle of an animal. Lab-grown protein companies claim that their products give consumers the opportunity to consume a protein product that does not come directly from an animal but is rather grown from animal cells. Such a product can, at best, be classified as a ‘meat byproduct’ or ‘meat food product.’ To be clear, several in the scientific community have asserted that cultured muscle tissue is not technically meat as the latter is also a product of postmortem biochemistry.”
Source: Cell-Cultured Meats Should be Distinctly Labeled, Ag Groups Tell USDA in Comments