diff --git a/4-make-yomitan.js b/4-make-yomitan.js
index 029eebe..47d11de 100644
--- a/4-make-yomitan.js
+++ b/4-make-yomitan.js
@@ -512,6 +512,8 @@ function normalizeOrthography(term) {
         case 'sga':
         case 'grc':
             return term.normalize('NFD').replace(/[\u0300-\u036f]/g, '');
+        case 'sh':
+            return term.normalize('NFD').replace(/[aeiourAEIOUR][\u0300-\u036f]/g, (match) => match[0]);
         case 'ru':
             return term.replace(/́/g, '');
         default: