We build a diminutive by adding the suffix -lein or -chen. For some nouns one is preferred over the other whereas with other nouns both may be used. Examples: der Tisch | das Tischlein | das ...
The suffix "-chen" is used as a diminutive, but a "standard" rabbit is already called a "Kaninchen", with the diminutive. How do you say "small rabbit" then? Ein Kaninchenlein or simply Ein ...
The German Wikipedia article on diminutive features a section on “Verselbständigte Diminutive”. These words all have conventional meaning, i.e. they are listed in a dictionary by themselves and not as ...