diff --git a/src/cco-extensions/ModalRelationOntology.ttl b/src/cco-extensions/ModalRelationOntology.ttl
index 9d40dc6..2a9e024 100644
--- a/src/cco-extensions/ModalRelationOntology.ttl
+++ b/src/cco-extensions/ModalRelationOntology.ttl
@@ -2015,7 +2015,7 @@ mro:ont00001904 rdf:type owl:ObjectProperty ;
                 rdfs:domain obo:BFO_0000001 ;
                 rdfs:range cco:ont00001163 ;
                 rdfs:label "is measured by"@en ;
-                skos:definition "y is_measured_by x iff x is an instance of Measurement Information Content Entity and y is an instance of Entity and y measures x."@en ;
+                skos:definition "y is_measured_by x iff x is an instance of Measurement Information Content Entity and y is an instance of Entity and y is_a_measurement_of x."@en ;
                 cco:ont00001760 <https://www.commoncoreontologies.org/ModalRelationOntology> .