There are lots of information on why words for animals are Anglo-Saxon, while their corresponding meats are French in origin. The most prominent examples are cow vs beef and pig vs pork.
My very limited understanding of French is that while some animals have the same words for their flesh (pigeon, goat, sheep), cows and pigs (and deer?) have different words (vache vs boeuf and cochon vs porc). Please correct if I am wrong. Like I said, my understanding of French is very limited.
So why are there different words in French? (Also, squab is le pigeonneau in French, so where did the word squab come from?)
The reason behind English having different words is so intertwined with history, so it made me interested in finding out why this is also the case in French for certain words. I tried to find answers on my own, but I keep finding more articles about how there different words in English.
Edit. The word squab is Scandinavian in origin. I'm interested why this particular word is Scandinavian while other meat words are French. But that was really an add-on question. (Maybe I should make a seperate post?)
I'll try and answer that one. I have the knowledge but explaining it in english will be a bit approximative since I'm French. Also, in advance, pardon my english (Ha ! Hum).
We DO have different words for the animal and the meat, but it's really specific and the vache / bœuf and cochon / porc distinctions are actually a rarity in case of animal / meat names - the other animals ar more straightforward. I'll also add that bœuf and porc can be animals too (but using vache and cochon for the meat is seen as childish).
It all comes, as often in French, from latin. It's because the meat comes from generic names, that were used for male and female animals - wich is understandable since when you eat the meat you don't really care about the sex of the animal... Boeuf is from bos, bovis, both genders possible ; porc is from porcus, also male and female (to speak about the female, Caton uses « porcus femina », for instance). Then, by metonymy, it became the meat of the animal. vache is from « vacca » which is the female of the bull, so it's specific. We're not really sure where cochon comes from, there is different theory but the general concensus (presented by Alain Rey, notably), is that it's from an onomatopoeia, and it came later (XI century).
As a French native speaker I think you are mistaken. Meat and animal from which it comes do have the same name in French (contrarily to English). Boeuf and porc are also used for the animals. Boeuf is a castrated male cow. Porc and cochon can be used for the animal interchangeably (they can have slightly different meanings when used figuratively for a person, though)
Ely van gelderen answers this question in her book "the history of the English language"
The different names correspond to whether the animal being spoken about is referring to the animal or the meat it produces. English adopted the meat names because that's what the French brought over-- ie, nobels would ask for the meat, and so the word was adopted into the common language.
The same isn't true for the animal itself, or for more rare meats.
If you're asking why the French invented different terms for it in the first place, then it most likely links back to the same reason English has variant reasons: separate lingual influences having differentiated meanings, like cheval (low vulgar Latin origins) vs equine (classical Latin origins).
In the cow example, vacca is cow in Latin while bof is ox. Over years and years vache became cow and boef became cow meat.