noun
Refers to beauty that is inherent or created by nature, not artificial. Often used in literary or aesthetic contexts.
この庭園は天成の美を感じさせる。
This garden evokes a sense of natural beauty.
Compound of 天成 (てんせい, 'heaven-made; natural') and 美 (び, 'beauty'). The exact historical derivation is uncertain, but the phrase is conventionally associated with the idea of beauty bestowed by nature.