Full Idea
A statement expressing a real definition must also accomplish more than simply to offer two different ways of singling out the same entity, since the definiens must also be explanatory of the essential nature of the definiendum.
Gist of Idea
Real definitions don't just single out a thing; they must also explain its essence
Source
Kathrin Koslicki (Varieties of Ontological Dependence [2012], 7.4)
Book Reference
'Metaphysical Grounding', ed/tr. Correia,F/Schnieder,B [CUP 2012], p.198
A Reaction
This is why Aristotelian definitions are not just short lexicographical definitions, but may be quite length. Effectively, a definition IS an explanation.
Related Idea
Idea 17313 Modern views want essences just to individuate things across worlds and times [Koslicki]