diff --git a/src/inflection.ts b/src/inflection.ts
index 7ae0d0f..0cd03c9 100644
--- a/src/inflection.ts
+++ b/src/inflection.ts
@@ -534,7 +534,7 @@ const singularRules: [RegExp, string?][] = [
   [regex.plural.nuclei, '$1us'],
   [regex.plural.nucleuses, '$1us'],
   [regex.plural.tia, '$1um'],
-  [regex.plural.analyses, '$1$2sis'],
+  [regex.plural.analyses, '$1sis'],
   [regex.plural.hives, '$1ve'],
   [regex.plural.curves, '$1'],
   [regex.plural.lrves, '$1f'],
diff --git a/test/inflection.test.ts b/test/inflection.test.ts
index b8f2b10..2e0a16c 100644
--- a/test/inflection.test.ts
+++ b/test/inflection.test.ts
@@ -111,6 +111,9 @@ describe('test .singularize', function () {
     expect(inflection.singularize('nuclei')).toEqual('nucleus');
     expect(inflection.singularize('nucleuses')).toEqual('nucleus');
     expect(inflection.singularize('nucleus')).toEqual('nucleus');
+    expect(inflection.singularize('analyses')).toEqual('analysis');
+    expect(inflection.singularize('bases')).toEqual('basis');
+    expect(inflection.singularize('diagnoses')).toEqual('diagnosis');
   });
 });