noun, na-adjective, noun which may take the genitive case particle 'no'
unparalleled in the present age; unrivaled today
A somewhat formal or literary four-character compound meaning that nothing or no one in the current era can match the subject. Often used in praise or historical commentary.
His skill is said to be unparalleled in this age.
It was acclaimed as a masterpiece without equal in the present era.
空前絶後 means 'unprecedented and never to be repeated', spanning past and future, while 当代無比 focuses specifically on being unmatched in the current era.
無双 is a more common word for 'peerless' or 'unmatched', used in both modern and historical contexts, whereas 当代無比 is more formal and explicitly tied to the present age.
A Sino-Japanese compound of 当代 (present age) and 無比 (unparalleled). The exact historical derivation is uncertain, but it follows a common pattern of four-character idiomatic expressions.