A collection of collections. Each instance of type of object is a specialization of tangible thing (q.v.). Moreover, each instance of type of object is a collection that is temporally stuff-like (see type of temporally stuff-like thing) but physically-spatially object-like (see type of object) -- i.e. object-like with respect to some physical-spatial part-whole predicate (e.g. some specialization of Proper Physical Decompositions).

Consider the collection book. book is a specialization of tangible thing. Further, book is temporally stuff-like: any one of the Time Slices of a given copy COPY of (say) Moby Dick is still a copy of Moby Dick . (Most collections of tangible objects are temporally stuff-like in this way.) But book is spatially object-like: if we take a scalpel and slice COPY into ten pieces, each piece is not a copy of Moby Dick . So book is an instance of type of object.

See also type of stuff and type of temporally and spatially stuff-like thing.