dreieckigem

Dreieckigem is the dative singular form of the German adjective dreieckig, meaning triangular or triangle-shaped. In German grammar, adjectives decline to agree with the nouns they describe; dreieckigem appears before masculine or neuter nouns in the dative case when there is no determiner that would trigger a weaker ending.

Etymology and form: The adjective dreieckig is derived from Dreieck (triangle) plus the suffix -ig, indicating a characteristic. The dative singular masculine or neuter form without a determiner carries the strong ending -em, yielding dreieckigem.

Usage: Dreieckigem is commonly found before masculine or neuter nouns in the dative case without a determiner. Examples include auf dreieckigem Grund (on triangular ground), mit dreieckigem Rand (with triangular edge), or in dreieckigem Stil (in triangular style). When a definite article or a determiner requiring weak inflection is used, the form changes to dreieckigen in the dative plural or to other weak endings in the singular, as in dem dreieckigen Rand (with definite article, dative masculine).

Notes: The form dreieckigem is not a standalone word but a grammatical inflection of the adjective dreieckig. In contrast, the corresponding weak endings appear with definite articles or possessive determiners (for example, dem dreieckigen Rand). The base adjective dreieckig is commonly used in geometry, design, heraldry, and branding to describe anything triangle-shaped or polygonal.