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A reference to the very small diameter of a strand of hair: compare hair's breadth.
Etymology from Wiktionary, CC BY-SA 4.0.
to a hair
Today it means: To a high degree of precision; with the utmost exactness; to a nicety. Full definition →
Today it means: To a high degree of precision; with the utmost exactness; to a nicety. Full definition →
A reference to the very small diameter of a strand of hair: compare hair's breadth.
Etymology from Wiktionary, CC BY-SA 4.0.