Creationists: Serious inquiry, can you provide me a *concrete,* non-shifting definition of the word “kind”?

I often hear how God created each “kind” of animal, or that Noah did not take every *specific* animal, but just a pair of each “kind.” And I often hear about the acceptance of micro-evolution (“adaptation within its kind”), but not macro-evolution because one “kind” of animal cannot become another “kind” of animal. However, Creationists [...]