diff --git a/lib/mixins/property-effects.html b/lib/mixins/property-effects.html
index 8e7d182283..90879a117c 100644
--- a/lib/mixins/property-effects.html
+++ b/lib/mixins/property-effects.html
@@ -1479,14 +1479,14 @@
        *
        * @param {Object} props Bag of one or more key-value pairs whose key is
        *   a property and value is the new value to set for that property.
-       * @param {boolean=} setPrivate When true, any private values set in
+       * @param {boolean=} setReadOnly When true, any private values set in
        *   `props` will be set. By default, `setProperties` will not set
        *   `readOnly: true` root properties.
        * @public
        */
-      setProperties(props, setPrivate) {
+      setProperties(props, setReadOnly) {
         for (let path in props) {
-          if (setPrivate || !this.__readOnly || !this.__readOnly[path]) {
+          if (setReadOnly || !this.__readOnly || !this.__readOnly[path]) {
             //TODO(kschaaf): explicitly disallow paths in setProperty?
             // wildcard observers currently only pass the first changed path
             // in the `info` object, and you could do some odd things batching