Another stab at defining namespace.

Author: ehuss

src/glossary.md

@@ -144,10 +144,13 @@ identifiers, and labels are used to refer to an entity.
 
 ### Namespace
 
-A [*namespace*] is a set of [names](#name) where each name unambiguously
-refers to a specific [entity](#entity). Namespaces are organized in a
-hierarchy, where each level of the hierarchy has its own collection of named
-entities.
+A *namespace* is a logical grouping of declared [names](#name) based on the
+kind of [entity](#entity) the name refers to. Namespaces allow the occurrence
+of a name in one namespace to not conflict with the same name in another
+namespace.
+
+Within a namespace, names are organized in a hierarchy, where each level of
+the hierarchy has its own collection of named entities.
 
 ### Nominal types
 

src/names/namespaces.md

@@ -1,8 +1,12 @@
 # Namespaces
 
-A *namespace* is a set of [names] where each name unambiguously refers to a
-specific [entity]. Namespaces are organized in a hierarchy, where each level
-of the hierarchy has its own collection of named entities.
+A *namespace* is a logical grouping of declared [names]. Names are segregated
+into separate namespaces based on the kind of entity the name refers to.
+Namespaces allow the occurrence of a name in one namespace to not conflict
+with the same name in another namespace.
+
+Within a namespace, names are organized in a hierarchy, where each level of
+the hierarchy has its own collection of named entities.
 
 There are several different namespaces that each contain different kinds of
 entities. The usage of a name will look for the declaration of that name in