Full Idea
Some properties are inseparable from the things to which they belong - as are length, breadth and depth from bodies, for without their presence it is impossible to perceive Body.
Gist of Idea
Some properties are inseparable from a thing, such as the length, breadth and depth of a body
Source
Sextus Empiricus (Against the Logicians (two books) [c.180], I.270)
Book Reference
Sextus Empiricus: 'Against the Logicians', ed/tr. Bury,R.G. [Harvard Loeb 1997], p.145
A Reaction
For the opposite case he suggests a man running, talking or sleeping. He doesn't mention essential natures, but this is clearly correct. We might say that they are properties which need to be mentioned in a full definition.