Simple Definition of hairline
: a thin line or crack
: the line where your hair starts on your forehead
Full Definition of hairline
1 : a very slender line: 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
Examples of hairline in a sentence
The plate had a hairline running across it.
He has a receding hairline.
First Known Use of hairline
Medical Definition of hairline
: the outline of scalp hair especially on the forehead
Seen and Heard
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