Pronunciation: (hâr'līn"), [key]
1. a very slender line.
2. the lower edge of the hair, esp. along the upper forehead: a hairline that slowly receded.
3. worsted fabric woven with very fine lines or stripes.
a. a very thin line on the face of a type. See illus. under type.
b. a style of type consisting entirely of such lines.
c. a thin rule for printing fine lines.
d. undesirable vertical lines between letters, caused by worn matrices.
narrow or fine as a hair: a hairline fracture.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.