diff --git a/ext/js/language/translator.js b/ext/js/language/translator.js
index 394e5eac..84ab0350 100644
--- a/ext/js/language/translator.js
+++ b/ext/js/language/translator.js
@@ -646,7 +646,8 @@ class Translator {
 
         for (const {expressions, frequencies: frequencies1, pitches: pitches1} of allDefinitions) {
             for (let i = 0, ii = expressions.length; i < ii; ++i) {
-                const {expression, reading, frequencies: frequencies2, pitches: pitches2} = expressions[i];
+                let {expression, reading, frequencies: frequencies2, pitches: pitches2} = expressions[i];
+                if (reading.length === 0) { reading = expression; }
                 let readingMap = expressionMap.get(expression);
                 if (typeof readingMap === 'undefined') {
                     readingMap = new Map();