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

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

Once a marker of lineage and tradition, a pinky ring is now the perfect platform on which its wearer signals their personal style—a tiny stage for diamonds, stacks, or just a single, simple gold band. —Malaika Crawford, Vogue, 25 Sep. 2025

Burials at national cemeteries proceed, along with related applications for headstones, markers, and burial benefits. —Aliss Higham, MSNBC Newsweek, 25 Sep. 2025

Researchers found that office workers who reduced their sitting time by adding periods of standing and light activity saw improvements in blood sugar levels and other health markers. —Jack McNamara, CNN Money, 25 Sep. 2025

The reopening will include Highway 67 to Forest Service Road W1 at about mile marker 11, plus Cape Royal Road. —Michael Salerno, AZCentral.com, 25 Sep. 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