noun, noun which may take the genitive case particle 'no'
unrivaled physical strength; peerless might
Describes a person of unmatched physical power, often in a heroic or exaggerated context. Can be used as a noun or with の to modify another noun.
彼は怪力無双の力士として知られている。
He is known as a sumo wrestler of unrivaled physical strength.
その戦士は怪力無双で、誰も敵わなかった。
That warrior had peerless might, and no one could match him.
A four-character compound combining 怪力 (superhuman strength) and 無双 (unrivaled). The exact origin is uncertain, but it follows a common pattern for describing exceptional qualities.