replace 'iteration' language

Author: gregsdennis

specs/jsonschema-core.md

@@ -417,9 +417,13 @@ they do not know how to process or explicitly choose not to process.
 
 ## Specification Versioning and Compatibility
 
-This specification is versioned by two values: iteration and release year.
+This specification is identified collectively by two values: version and release
+year.
 
-A schema written to conform with the requirements of a given version (iteration and release year) is compatible with specifications published with the same iteration value and either the same or greater release year value.  Thus, JSON Schema provides a guarantee of compatibility for future releases within an iteration.
+A schema written to conform with the requirements of a given version is
+compatible with successive specifications, which are published with the same
+version and either the same or greater release year value. Thus, JSON Schema
+provides a guarantee of compatibility for future releases within a version.
 
 ## Keyword Behaviors
 

specs/jsonschema-validation.md

@@ -90,9 +90,9 @@ specification.
 The current IRI for the default JSON Schema dialect meta-schema is
 `https://json-schema.org/1/2025`. This IRI encodes the specification's version
 and release year. Because all schemas written to conform to a given version are
-guaranteed to be compatible with later releases within the same iteration, the
+guaranteed to be compatible with later releases within the same version, the
 meta-schema IRI `https://json-schema.org/1` is also recognized to represent the
-latest release within the indicated iteration.
+latest release within the indicated version.
 
 The meta-schema describes a dialect consisting of all keywords defined in this
 specification and the JSON Schema Core specification. Certain keywords specify