hairline

noun

hair·​line ˈher-ˈlīn 

1

: a very slender line: such as

a

: a tiny line or crack on a surface

a hairline bone fracture

b

: a fine line connecting thicker strokes in a printed letter

2

: hairbreadth

3

a

: a textile design consisting of lengthwise or crosswise lines usually one thread wide

b

: a fabric with such a design

4

a

: the outline of scalp hair especially on the forehead

b

: the way the hair frames the face

hairline adjective

Synonyms of hairline

• inch
• hair
• neck
• step

Examples of hairline in a Sentence

The plate had a hairline running across it.

He has a receding hairline.

Recent Examples on the Web

Bolton said unsatisfied transplant recipients are coming to him with unnatural hairlines. —Cindy Krischer Goodman, Sun Sentinel, 9 Apr. 2026

Because hair tends to be thinnest at the hairline, Markenson says curtain bangs like Nicole Richie's are ideal for making that area appear fuller. —Ariel Wodarcyk, InStyle, 7 Apr. 2026

Sutskever, who was born in the Soviet Union in 1986, has a receding hairline, dark eyes, and a habit of pausing, unblinking, while choosing his words. —Ronan Farrow, New Yorker, 6 Apr. 2026

The rash usually begins as flat red spots that appear on the face at the hairline and spread downward to the neck, torso, arms, legs and feet. —Ashley J. Dimella, FOXNews.com, 3 Apr. 2026

Word History

First Known Use

1846, in the meaning defined at sense 1

Rhymes for hairline

• affine
• airline
• align
• aline
• assign
• baseline
• beamline
• benign
• bloodline
• bovine
• byline
• canine

Kids Definition

hairline

noun

hair·​line ˈha(ə)r-ˌlīn 

ˈhe(ə)r-

1

a

: a very slender line

b

: a very thin crack on a surface

a hairline bone fracture

2

: the outline of the hair on the head and especially on the forehead

hairline adjective

Medical Definition

hairline

noun

hair·​line -ˈlīn 

: the outline of scalp hair especially on the forehead

hairline adjective