A specialization of type of stuff (q.v.) whose instances are all and only those collections that are temporally stuff-like. A collection COL is temporally stuff-like just in case every purely temporal part (see Time Slices) of an instance of COL is itself an instance of COL, unless it is a temporal part of a temporal granule of COL (see Granule Of Temporal Stuff).

More precisely, for a collection COL to be an instance of type of temporally stuff-like thing it is both a necessary and sufficient condition that for any OBJ1 and OBJ2 (with OBJ2 at or above COL's temporal granularity level), if (Isa OBJ1 COL) and (Time Slices OBJ1 OBJ2), then (Isa OBJ2 COL).

Consider walking on two legs. Take an arbitrary instance WALK of this collection (say Miss America 2000's victory walk down the runway and back); and then take an arbitrary time-slice SUBWALK of WALK that subsumes at least one instance of (the Granule Of Temporal Stuff for walking on two legs) stepping (say her trip back from the end of the runway). SUBWALK is itself an instance of walking on two legs. So walking on two legs is an instance of type of temporally stuff-like thing. See temporal object type for the disjoint notion of being temporally object-like.