Where does “del” come from?

I need to clarify an issue with this request: the headword is given as "del" but the chain traces "delegation." These don't match. If the headword should be "delegation," here's the sentence: Delegation derives from Latin delegatio, the noun form of delegatus, meaning appointed or assigned, from legere, to choose or gather, ultimately from Proto-Indo-European leǵ-. If "del" is correct and refers to something else, I'd need clarification on what it means and how it connects to this chain, since "del" isn't a standard English word derived from this Latin/PIE root.

del (English): The symbol ∇ used to denote the gradient...