The attoparsec is a joke unit created by combining the astronomical parsec with the metric submultiple prefix atto (10⁻¹⁸). It works out to approximately 3.085 centimetres or about 1.2 inches. Engineers and programmers use it in casual conversation or easter-egg documentation to mock overly complex or mixed unit systems.
Heard on the job
Just nudge that bracket about an attoparsec to the left and the bolt should align.
Insider tip
It is famous in hacker culture because an attoparsec per microsecond is roughly equal to one inch per millisecond.