na-adjective
Used in academic, technical, or formal contexts to describe something that objectively describes facts or phenomena without prescribing norms.
この論文は記述的な分析に重点を置いている。
This paper emphasizes descriptive analysis.
記述的な文法は、実際の言語使用を
Descriptive grammar derives rules by observing actual language use.
From 記述 (description) + 的 (-like, -ive). The exact historical derivation is uncertain, but the word follows a common pattern for forming adjectival nouns from Sino-Japanese nouns.