Defining requires prior knowledge of a thing’s properties before selecting which ones matter.

Evidence

To define a thing, is to select from among the whole of its properties those which shall be understood to be designated and declared by its name; the properties must be very well known to us before we can be competent to determine which of them are fittest to be chosen for this purpose. — Gary Goertz, Social Science Concepts and Measurement, 26

Categorization

• DEFINE: A precise classical statement of what defining is: selection from a thing’s properties.
• APHORISMS: Reads as methodological counsel: know the whole before you pick the parts worth naming.