Thank you, I had the German word in mind and was not able to find the English one in my foggy brain.
Were you thinking of „Verkleinerungsform“? Do people still use those Germanized terms? It feels a little old-fashioned to me, like saying „besitzanzeigendes Fürwort“ instead of Possessivpronomen.
In a way? I always found it more sensible to use German words like "Namenwort" instead of "Nomen" to express German grammar, instead of using latin terms. After all Latin is a language that comes from a completely different language family to start with and is not used at all in Germany except when wanting to pretend you're fancy (law, medicine, grammar).
I now accept that I am losing my French while not being really fluent in any other language.