corner rounder; corner cutter
Refers to a tool or device used to round off sharp corners, typically on paper or card stock.
I used a corner rounder to round the corners of the business cards.
rounding corners (in bookbinding)
The process or action of rounding the corners of pages, especially during bookbinding or finishing.
rounded corners
The state or feature of having rounded corners, often on printed materials or UI elements.
The icons in this app are characterized by their rounded corners.
Rounding the corners during the bookbinding process makes the book corners less prone to damage.
Compound of 角 (corner) and 丸 (round). The exact historical derivation is uncertain, but the meaning is transparent from its components.