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

• ace
• hair
• hairbreadth
• hairsbreadth
• hop, skip, and jump
• inch
• neck
• shouting distance
• step
• stone's throw

Examples of hairline in a Sentence

The plate had a hairline running across it.

He has a receding hairline.

Recent Examples on the Web

Seemingly, this was the equivalent to modern day hairline lasering–a treatment at least one Kardashian has confessed to. —Jennifer Adams, StyleCaster, 19 May 2025

While baldness, thinning, and hairline woes are more commonly associated with men, female pattern hair loss is estimated to impact 40 percent of women before age 50. —Maria Yagoda, Vox, 9 May 2025

In March 2024, hairline cracks began forming along the entire length of a support beam on the top floor. —Susannah Bryan, Sun Sentinel, 6 May 2025

This mineral sunscreen has a brush applicator that’s easy to apply to your part and hairline. —Rebecca Shinners, Travel + Leisure, 5 May 2025

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