diaeresis or dieresis /dī-ērˈi-sis or -erˈ/

1. A mark ( ¨ ) placed over a vowel, esp the second of two adjacent ones to show that it is to be pronounced separately, as in naïf
2. A pause or break where the end of the word coincides with the end of a foot (prosody)

• inmarriages
• INMARSAT
• Inmarsat
• in mass
• inmate
• inmates
• in medias res
• in memoriam
• in mesh
• inmesh
• inmeshed
• inmeshes
• inmeshing
• inmeshment
• in microcosm
• in midstream
• in milk
• in miniature
• inmost
• in mothballs
• in mourning
• in my book
• in my etc book
• in my voice
• inn