diff --git a/src/cco-extensions/ModalRelationOntology.ttl b/src/cco-extensions/ModalRelationOntology.ttl
index 41e1123..6b381bb 100644
--- a/src/cco-extensions/ModalRelationOntology.ttl
+++ b/src/cco-extensions/ModalRelationOntology.ttl
@@ -1035,7 +1035,7 @@ mro:ont00001808 rdf:type owl:ObjectProperty ;
                 rdfs:domain cco:ont00000958 ;
                 rdfs:range obo:BFO_0000001 ;
                 rdfs:label "is about"@en ;
-                <http://www.w3.org/2004/02/skos/core#definition> "A primitive relationship between some instance of Entity x and an instance of Information Content Entity y."@en ;
+                <http://www.w3.org/2004/02/skos/core#definition> "x is_about y iff x is an instance of Information Content Entity and y is an instance of Entity such that the information content of x depends on the existence of y. A primitive relationship."@en ;
                 cco:ont00001754 "http://purl.obolibrary.org/obo/IAO_0000136" ;
                 cco:ont00001760 <https://www.commoncoreontologies.org/ModalRelationOntology> .