trema

Etymology

Ancient Greek τρῆμα (trêma, “hole”), from τετραίνω (tetraínō, “perforate”), used for the dots on dice, via Dutch trema and French tréma.

noun

1. A diacritic consisting of two dots ( ¨ ) placed over a letter, used among other things to indicate umlaut or diaeresis.
2. "an initial phase in the psychotic process that is characterized by intense anguish, an experience of hostility and a feeling of imminent catastrophe".