From parshat Vayeitzei:
kohanim, descendants of Aharon, are so called because of their function of ministering. (Elsewhere, the Netinim are given over to serve, and are so called because of their function.) And the typical Levites are joined unto the kohanim, to minister under them -- וְיִלָּווּ עָלֶיךָ. And two pesukim later:
perhaps they are so called because of their function.
This is readily dismissible, if need be, as a simple pun in parshat Korach, drawing on Levi's name to describe shevet Levi's role, something which the Biblical text frequently does.