material_entity object Definition: A material entity [snap:MaterialEntity] that is spatially extended, maximally self-connected and self-contained (the parts of a substance are not separated from each other by spatial gaps) and possesses an internal unity. The identity of substantial object [snap:Object] entities is independent of that of other entities and can be maintained through time. Examples: an organism, a heart, a chair, a lung, an apple Synonyms: substance object_aggregate object_boundary site