Definition
A hand file with a circular cross-section, used by aircraft mechanics to smooth, enlarge, or shape the inside of round holes and curved surfaces.
Plain English
A long, pencil-shaped metal tool with a rough surface, used to smooth or slightly enlarge round holes.
Context Anchor
You may hear this informal phrase around maintenance shops, flight schools, dispatch desks, or offices when people are talking about paperwork.
Derivation
The phrase comes from office slang. A normal file stores papers for later use; a wastebasket was often round, so calling it the “round file” is a joking way to say the paper is being filed in the trash.
Why Pilots Care
Pilots and mechanics must know the difference between informal paperwork and required records. A required logbook entry, inspection record, checklist change, or official notice should never be treated as something for the round file.
Intuition Check
Do not read this as a special aviation file or a circular folder. It is informal slang for throwing something away.
Example Sentence 1
The mechanic used a round file to deburr the freshly drilled hole before installing the rivet.
Example Sentence 2
Before you toss that logbook page in the round file, make sure the entry is copied to the permanent records.