umlaut /ŭmˈlowt/

1. A vowel change in Germanic languages brought about by a vowel or semivowel (esp i or j, usu now lost) in the following syllable
2. The diacritical sign (¨), dots placed over a vowel, indicating such a modification

To modify (a vowel) with an umlaut

• err on the safe side
• error
• errorist
• errorists
• errorless
• error message
• error messages
• errors
• hanger-on
• hanger-ons
• hangers
• hangers-on
• hang fire
• hangfire
• hangfires
• hang-glide
• hang-glided
• hang-glider
• hang-gliders
• hang-glides
• hang-gliding
• hangi
• hang in
• hang in effigy
• hanging