unregelhaftem

Unregelhaftem is the dative singular form of the German adjective unregelhaft, meaning irregular or not following regular rules. It appears before masculine or neuter nouns in the dative case, especially in contexts without a definite determiner or after certain prepositions.

In German grammar, attributive adjectives are declined to match case, gender, and number. When the adjective appears in the dative singular before a masculine or neuter noun, the strong declension yields forms such as unregelhaftem. Examples include in unregelhaftem Verhalten (in irregular behavior) and in unregelhaftem Muster (in an irregular pattern). The form signals that the noun it modifies does not conform to a standard rule or pattern in the given context.

The term is widely used in linguistics, grammar descriptions, and technical writing to describe irregularities in processes, systems, or language forms. In everyday German, speakers often prefer the more common adverbial or adjectival forms like unregelmäßig for describing regularity in a general sense; unregelhaft is sometimes used to emphasize structural irregularity or to describe specific irregularities rather than general irregularity.

Etymology: unregelhaftem derives from un- (negation) + regelhaft (having the quality of a rule or regularity), with the suffix -em marking the dative masculine or neuter singular form in strong declension. The broader root is regel, “rule,” connected to terms describing regularity and pattern.