The word evolution is about change not origin. Change can be studied without regard to origin.
I'd avoid it too if I were you. There is no way to bob and weave around the plain definitions of the words.
How can agnostics and atheists challenge Christians with silly questions like "who made God" and "how can God be infinite" when you can't answer the same questions about our universe?
I guess you'll have to find some and ask them.