You searched for: “areni-”
arena [harena], areni-
Latin: sand, sandy place, sea-shore; place of combat [literally, "place strewn with sand"]; gives us arena with two important descriptive parts.
The arena and areni- element is often heard but few know its origins; however, this list and the two arena parts will give you perspectives that will clarify how the word became a part of English:
A unit related to: “areni-”