Why does Nun have an Aramaic name?
Nun, the father of Yehoshua, is apparently named after a word for fish in Aramaic (for example, Beresheet Rabbah 97:3; Divrei Emet, Matot). His father Elishama (according to Divrei Hayamim 1:7:26-27) had a Hebrew name. His son Yehoshua had a Hebrew name. Arguably, all of Ephraim's descendants (prior to Nun) have Hebrew names. Why does Nun have an Aramaic name?
Something to consider: If it's because Elishama wanted to give his son a non-Hebrew name, wouldn't an Egyptian name make more sense?