HAIRBREADTH

Etymology

Noun

hairbreadth (plural hairbreadths)

the width of a hair, a very short distance or a very small amount

Measure Maddalena, and measure Minerva, and from forehead to chin, you won't find a hairbreadth of difference between them.

Source: Wiktionary

Hair"breadth`, Hair's"breadth`, a.

Definition: The diameter or breadth of a hair; a very small distance; sometimes, definitely, the forty-eighth part of an inch. Every one could sling stones at an hairbreadth and not miss. Judg. xx. 16

Hair"breadth`, a.

Definition: Having the breadth of a hair; very narrow; as, a hairbreadth escape.

Source: Webster’s Unabridged Dictionary 1913 Edition