Definitions

1. noun

A thing of exceptional quality or excellence; something unrivaled or unmatched.

“This new smartphone is the nonsuch in its class.”

2. noun

A ship or other vessel that was considered to be the best or most excellent of its kind.

“The nonsuch of the British Navy was flagship of the fleet.”

3. adjective

Unmatched or unrivaled in quality or excellence.

“He was a nonsuch among his peers for his exceptional skills.”