Gnat's Ass Edit Meaning

1.

Very small measurement used by toolmakers & engineers, or roughly .0001 or one ten thousandth of an inch. Actual size may vary between shops, but always much less than a pussy hair. About one tenth of a skoshwhich is equal to approximately one nudge of the dial.

Note: When specified, generally regarded as smaller than the smallest one can measure or produce, since while most people intuitively understand that a gnat's ass is pretty small, few have actually bothered a gnat to measure one.

"Clearance is clearance, Clarance, but that die is only missing by a gnat's ass".

See clearance, tool, die, machinist, small, gnat, ass