Full Idea
Intrinsic properties are, by and large, those properties that an object can exemplify even if that object and its parts (if any) are the only objects that exist.
Gist of Idea
Intrinsic properties are those an object still has even if only that object exists
Source
Trenton Merricks (Objects and Persons [2003], §4.I)
Book Reference
Merricks,Trenton: 'Objects and Persons' [OUP 2003], p.92
A Reaction
This leads to all sorts of properties that seemed intrinsic turning out to be relational. In what sense would a single object have mass, or impenetrability?