n.
Pronunciation: - ' l ī n
Function: noun
Date: 1846
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
– hairline adjective