noun
dan rank holder; black belt; dan player
Refers to a person who holds a dan rank in martial arts, board games like go or shogi, or other graded systems. Often used specifically for black belts in martial arts.
See also: 段
彼は柔道の有段者だ。
He is a black belt in judo.
囲碁の有段
I played a game against a dan-ranked go player.