Noun
a very small distance or space
Source: WordNetMark how fleeting and paltry is the estate of man - yesterday in embryo, tomorrow a mummy or ashes. So for the hairsbreadth of time assigned to thee, live rationally, and part with life cheerfully, as drops the ripe olive, extolling the season that bore it and the tree that matured it. Marcus Aurelius
they escaped by a hair's-breadth Source: Internet
they lost the election by a whisker Source: Internet