marker

noun

mark·​er ˈmär-kər 

1

: one that marks

2

: something used for marking: such as

a

: a type of felt tip pen that makes wide lines

drew a tree with green and brown markers

used a permanent marker to label the boxes

b

: any of various sewing devices for making or indicating guidelines

a pin marker for hemlines

3

: score sense 7

specifically : run

4

: promissory note, iou

5

: something that serves to identify, predict, or characterize: such as

a

: biomarker

b

: genetic marker

Synonyms

• label
• tag
• ticket

Examples of marker in a Sentence

A person's accent can be a marker of social class.

the markers on the rock and mineral specimens were old and faded

Recent Examples on the Web

These details are contrasted by rose gold hour markers and hands—including the small seconds and date hands. —Anthony Demarco, Forbes.com, 1 Apr. 2025

Two versions are available: one with turquoise varnish and white Super-LumiNova markers, paired with a black rubber strap featuring turquoise stitching; the other with gray varnish and gray Super-LumiNova markers, paired with a strap featuring a gray underside. —Renan Botelho, Footwear News, 1 Apr. 2025

And just weeks later, the actress Hunter Schafer revealed in an eight-minute social media post that her passport gender marker was changed to male by the State Department without her consent or knowledge. —Larisha Paul, Rolling Stone, 31 Mar. 2025

Crayola Clicks Retractable Tip Markers These best-selling markers feature a cone tip that allows for both fine lines and broad strokes, and they can be retracted with a simple click, so there’s no need to hunt down missing caps. —Mia Huelsbeck, People.com, 29 Mar. 2025

Word History

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing marker

• genetic marker

Rhymes for marker

• barker
• darker
• starker
• biomarker

Kids Definition

marker

noun

mark·​er ˈmär-kər 

1

: one that marks

2

: something used for marking

Medical Definition

marker

noun

mark·​er ˈmär-kər 

: something that serves to identify, predict, or characterize

a surface marker on a cell that acts as an antigen

: as

a

: biomarker

The recent discovery of a serological marker for the hepatitis C virus has greatly improved diagnostic accuracy for this form of hepatitis.

—Gary P. Wormser, letter in The Journal of the American Medical Association

b

: genetic marker

The idea in genetic linkage analysis is to see if any particular marker, which serves as a signpost for a specific region of a chromosome, is consistently inherited along with the disease …

—Leslie Roberts, Science

called also marker gene