Full Idea
We can assign a term to any 'account' whatever, so that the Iliad would be a definition! No, a definition must be of something primary.
Gist of Idea
A definition must be of something primary
Source
Aristotle (Metaphysics [c.324 BCE], 1030a08)
Book Reference
Aristotle: 'Metaphysics', ed/tr. Lawson-Tancred,Hugh [Penguin 1998], p.180
A Reaction
At first hearing you may doubt this claim, but Aristotle's example clinches it beautifully. Are you really going to say that The Iliad is the definition of 'Iliad'?