I'm not sure, I've used 'fn' in toy programming language concepts before I ever heard of arc or clojure. I mean, its not impossible and I certainly don't know a

I'm not sure, I've used 'fn' in toy programming language concepts before I ever heard of arc or clojure. I mean, its not impossible and I certainly don't know about the others, but its also not impossible that they were independently named. However, I do think its very likely that arc influenced Clojure, even if just a little.