I think you're understanding is correct as far as the way geneticists use the term but it isn't unprecedented to use it to describe generations from the wild. I believe Ross and Marzec in "Reproductive Husbandry of Pythons and Boas" suggested it be used that way in Species Survival Plan studbooks and by private herpetoculturists.

Either way it's very useful for alterna breeders. Maybe we should start using W1, W2, W3, ect. instead?
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