diff --git a/source/core/data-model-design.txt b/source/core/data-model-design.txt
index 61f7881bb91..01dead81d98 100644
--- a/source/core/data-model-design.txt
+++ b/source/core/data-model-design.txt
@@ -79,7 +79,7 @@ In general, use normalized data models:
 References provides more flexibility than embedding. However,
 client-side applications must issue follow-up queries to resolve the
 references. In other words, normalized data models can require more
-roundtrips to the server.
+round trips to the server.
 
 See :ref:`data-modeling-publisher-and-books` for an example of
 referencing. For examples of various tree models using references, see