Relating to nature or occurring/being produced naturally; indicates something natural. (In everyday Japanese, '自然な' is more common.)
この配置は見た目に自然的で、違和感がない。
This arrangement looks natural and doesn't feel awkward.
進化の過程で生じた自然的な変化を観察する。
Observe natural changes that occurred during the course of evolution.
文章は自然的な流れを保つことが重要だ。
It's important for writing to maintain a natural flow.