I have noticed that some older cookbooks use the term 'receipt' in place of 'recipe'. Why did this change occur?
I tried looking up usage of both recipe and receipt using Google Books' NGram viewer, but I'm afraid I got a lot of false positives on 'receipt' because that word is used in so many other non-food-related contexts.
That said, for the word 'recipe' there was a sharp incline after about 1967, and a corresponding (although less dramatic) decrease in the use of the word 'receipt'.
I believe both words must have been in common usage in about 1950, at least where I live in the southern United States, because I have two cookbooks dated to around then which are both collections of recipes local to where each of my grandmothers lived, "Charleston Receipts" and "River Road Recipes".
I'm curious if any of you know more about these two words and why the sudden preference of one over the other.