noun which may take the genitive case particle 'no', na-adjective, noun
eternal; everlasting; timeless
Describes something that continues unchanged for an extremely long time, often with a poetic or formal tone. Used for nature, history, or abstract concepts.
悠久の時を経て、その神殿は今も残っている。
Having passed through eternal time, the temple still remains today.
この山々は悠久の美しさをたたえている。
These mountains possess a timeless beauty.