diff --git a/src/owl/bfo-core.ofn b/src/owl/bfo-core.ofn
index 05059e0..203abae 100644
--- a/src/owl/bfo-core.ofn
+++ b/src/owl/bfo-core.ofn
@@ -778,7 +778,7 @@ SubClassOf(<http://purl.obolibrary.org/obo/BFO_0000035> ObjectAllValuesFrom(<htt
 
 AnnotationAssertion(dc11:identifier <http://purl.obolibrary.org/obo/BFO_0000038> "103-BFO")
 AnnotationAssertion(rdfs:label <http://purl.obolibrary.org/obo/BFO_0000038> "one-dimensional temporal region"@en)
-AnnotationAssertion(skos:definition <http://purl.obolibrary.org/obo/BFO_0000038> "(Elucidation) A one-dimensional temporal region is a temporal region is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts"@en)
+AnnotationAssertion(skos:definition <http://purl.obolibrary.org/obo/BFO_0000038> "(Elucidation) A one-dimensional temporal region is a temporal region that is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts"@en)
 AnnotationAssertion(skos:example <http://purl.obolibrary.org/obo/BFO_0000038> "The temporal region during which a process occurs"@en)
 SubClassOf(<http://purl.obolibrary.org/obo/BFO_0000038> <http://purl.obolibrary.org/obo/BFO_0000008>)
 SubClassOf(<http://purl.obolibrary.org/obo/BFO_0000038> ObjectAllValuesFrom(<http://purl.obolibrary.org/obo/BFO_0000121> ObjectUnionOf(<http://purl.obolibrary.org/obo/BFO_0000038> <http://purl.obolibrary.org/obo/BFO_0000148>)))
diff --git a/src/owl/bfo-core.owl b/src/owl/bfo-core.owl
index dcfbd3a..e88a0c3 100644
--- a/src/owl/bfo-core.owl
+++ b/src/owl/bfo-core.owl
@@ -1941,7 +1941,7 @@
     <AnnotationAssertion>
         <AnnotationProperty abbreviatedIRI="skos:definition"/>
         <IRI>http://purl.obolibrary.org/obo/BFO_0000038</IRI>
-        <Literal xml:lang="en">(Elucidation) A one-dimensional temporal region is a temporal region is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts</Literal>
+        <Literal xml:lang="en">(Elucidation) A one-dimensional temporal region is a temporal region that is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts</Literal>
     </AnnotationAssertion>
     <AnnotationAssertion>
         <AnnotationProperty abbreviatedIRI="skos:example"/>
diff --git a/src/owl/bfo-core.ttl b/src/owl/bfo-core.ttl
index 8e39757..5d9d290 100644
--- a/src/owl/bfo-core.ttl
+++ b/src/owl/bfo-core.ttl
@@ -1034,7 +1034,7 @@ skos:scopeNote rdf:type owl:AnnotationProperty .
                                              owl:disjointWith <http://purl.obolibrary.org/obo/BFO_0000148> ;
                                              dc11:identifier "103-BFO" ;
                                              rdfs:label "one-dimensional temporal region"@en ;
-                                             skos:definition "(Elucidation) A one-dimensional temporal region is a temporal region is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts"@en ;
+                                             skos:definition "(Elucidation) A one-dimensional temporal region is a temporal region that is a whole that has a temporal interval and zero or more temporal intervals and temporal instants as parts"@en ;
                                              skos:example "The temporal region during which a process occurs"@en .