An ENTRY is the root of a logical item of hard clinical information created in the clinical statement context, within a clinical session or of clinical knowledge in a knowledge artifact.
With regards to clinical information entries, there can be numerous such contexts in a clinical session. Observations and other Entry types only ever document information captured/created in the event documented by the enclosing Composition.
An ENTRY is also the minimal unit of information any query should return, since a whole ENTRY (including subparts) records spatial structure, timing information, and contextual information, as well as the subject and generator of the information.