grundlegendere
Grundlegendere is a term that can appear in German-language texts as a comparative form related to the adjective grundlegend, meaning fundamental or essential. It is not a standard entry in major German dictionaries, and its use is generally considered nonstandard in formal writing. The normative comparative for grundlegend is grundlegender, with the superlative am grundlegendsten.
Etymology and usage notes: grundlegendere would be formed from grundlegend by adding a suffix resembling -ere
Practical guidance: in neutral, formal, or academic German, the preferred forms are grundlegender for the comparative
See also: grundlegend, grundlegend sein, fundamental. The discussion of this form highlights how German adjectives form