She is known as a master of the violin.
That player is an expert defender.
brilliant move; excellent move
Specialized use for an excellent move in games such as go or shogi. It refers to the move itself, not to a skilled player.
In the shogi commentary, that move was praised as a brilliant move.
A brilliant move in the endgame decided the match.
He is known as a master violinist.
He played a brilliant move in the endgame.
She is known as an expert in defense.
妙手 specifically names a clever or unexpectedly brilliant move in go or shogi, matching 名手's second sense of 'brilliant move'.
達人 conveys a deep, almost philosophical mastery, whereas 名手 is used more for practical excellence in performance, sports, or technique.
A Sino-Japanese compound of 名, associated here with excellence or reputation, and 手, associated with a person skilled by hand or a move in a game. The spelling transparently matches the modern meanings, though this is a component explanation rather than a detailed historical derivation.