What is "Stotterlaut"? Is this term used in the phonetics? If so, what sound exactly does it indicate? I guess that it might belong to one of the plosive or affricate sounds from the context, but I couldn't find any definition or enough reference. Thanks!
Stotterlaut itself is the sound you make when you stutter (literally stutter noise). This article mentions
Nun ist d nicht nur Verschluß-, Dental-Laut, sondern wie die Erfahrung ergibt, bei häufiger Wiederholung geradezu ein Stotterlaut
Now d is not only a plosive and dental sound, but as experience shows downright a stutter sound, when frequently repeated
This is illustrated with some examples, among which is the following
Die, die die Didaktik Diderots zum Gegenstand ihrer Studien machten [...]
The beginning of the sentence, which causes you to say /di/ 4 times, sounds like a stuttering person trying to say Didaktik.