Wiktionary
n. binder clip.
WordNet
n. a clip with a spring that closes the metal jaws [syn: alligator clip]
Wikipedia
A bulldog clip is a device for temporarily but firmly binding sheets of paper together. It consists of a rectangular sheet of springy steel curved into a cylinder, with two flat steel strips inserted to form combined handles and jaws. The user presses the two handles together, causing the jaws to open against the force of the spring, then inserts a stack of papers and releases the handles. The spring forces the jaws together, gripping the papers firmly.
A Bulldog clip combined with a suitable piece of board makes a clipboard.
Usage examples of "bulldog clip".
Teletape, pasted in strips on pink paper, hung in batches on the notice board, fastened with a heavy bulldog clip like galley proofs awaiting correction.
A WPC walked past and handed the Farmer a sheaf of telephone messages - so many they were held by a bulldog clip.
And the large bulldog clip over the hanger's bar, its teeth fastened in the loose, wrinkled skin of his walnut head, holding it up.