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

• reticule
• reticules
• reticulocyte
• reticulocytes
• reticulo-endothelial system
• reticulum
• retie
• retied
• reties
• retiform
• retile
• retiled
• retiles
• retiling
• retime
• retimed
• retimes
• retiming
• retina
• retina camera
• retina cameras
• retinacula
• retinacular
• retinaculum
• retinae