I downvoted because it's tiring and pedantic to raise the objection every time someone says "designed for" in the context of biology. Yeah, we get it: evolution has no designer. It doesn't matter, because the semantic space is well understood. The figure of speech "designed for X" just means it's narrowly optimal at X -- it's good at X at the expense of being bad at not X.

Hence explanations like, "A cat's digestive system is designed for meat: it has enzymes Q and Z which are really good at breaking down flesh but also react poorly to plant matter." We get the point. We don't need a reminder that, "well, the scientific consensus is that the cat digestive system arose without an intelligent designer".

That's a very good definition of "designed" that I hadn't seen before.

Thanks. I didn't mean to suggest it was a documented definition, so much as "the characteristic that makes it 'feel' like a human-designed thing" and makes us want to refer to it that way, even when knowing it wasn't.