What do you call this black, rectangular clamp in English?
Solution 1:
I think the term is bulldog clip:
- a small metal object that shuts tightly to hold papers together.
(source: Longman Dictionary of Contemporary English)
Bulldog clip (British)
- A strong sprung metal device with two flat plates that close so as to hold papers together.
(source: Oxford Dictionary) (British)
Solution 2:
Binder clip, also known as a foldback or banker's clip.
It is called a binder clip because the bent metal clips may be removed, creating a semi-permanent binding (see right).