na-adjective
Describes something in its earliest, most basic, or original state, often with a nuance of being undeveloped or fundamental. Used in formal or academic contexts.
この洞窟には原初的な壁画が残っている。
Primitive wall paintings remain in this cave.
宇宙の原初的な姿を研
They are researching the primordial state of the universe.
Compound of 原初 (gensho, 'origin; beginning') + 的 (-teki, '-like; -ic'). The exact historical derivation is uncertain, but the word follows a standard pattern for forming adjectival nouns from Sino-Japanese roots.