One who or that which marks.
- One that marks or serves as a mark, as:
- A bookmark.
- A tombstone.
- A milestone.
- An implement, especially a felt-tipped pen, used for marking or writing.
- One who marks objects, especially for industrial purposes.
- One who grades student papers.
- Sports A device, such as a line, stake, or flag, set on a playing field and showing the playing or scoring position.
- Sports A player who guards an opponent, as in soccer.
- Sports An official in certain court games, such as squash, who mainly judges whether the ball is out of play and whether a fault or let has occurred.
- Games One that keeps score in various games.
- Games A score in a game.
- Slang A written, signed promissory note.
- A genetic marker.
- Medicine A physiological substance, such as human chorionic gonadotropin or alpha-fetoprotein, that when present in abnormal amounts in the serum may indicate the presence of disease, as that caused by a malignancy. Also called biomarker.
- Linguistics An element that indicates grammatical class or function; a derivational or inflectional morpheme.