'tridens', 'tridentis', from 'tri', three, 'dens', tooth, 'dentes', teeth) is a three pronged staff.
It was used by fishermen to catch fishes.
From the fish meaning, it is often associated with Poseidon, the God of the sea in Greek mythology. By hitting the earth with his trident, Poseidon created the horse and some water sources in Greece.
As a sea symbol it is the central figure of the flag of Barbados.
The trident is also the missile weapon of the Hindu god Shiva, and it often includes a crossed stabiliser to facilitate its fly when thrown.
As a weapon it was also used by the retiarii, Roman gladiators that used a net to wrap their adversary and a trident to kill him.
In Christian tradition the trident is associated with the Devil, and his depictions commonly include a trident as his sceptre.