A trident. Though sometimes in the popular media a person can see a gladiator using a trident as a throwing weapon, this is all Hollywood dreaming. The trident was designed as a thrusting weapon and the person using it wouldn't throw it away any more than an opponent would throw away a shield.
Poseidon fought with a trident, a three-pointed spear.
spear
spear
A spear, or pointed object
a spear, a stake or perhaps an arrow.
It is a noun: "The man held a spear in his hand."It is also a verb: "He tried to spear the fish from the riverbank."
A wooden shaft and a spear head of sharply pointed iron.
Herons have long pointed beaks to spear fish.
Asparagus is a green "spear," about ten inches long, with pointed leaves forming a tip.
Some examples of plants with spear-shaped leaves include yucca, Sansevieria (snake plant), and agave. These plants are known for their long, pointed leaves that resemble a spear.
There were several types of gladiators. Only one type was armed with a net and a trident (three-pointed spear). He was meant to represent King Neptune, and his opponent in armour was meant to represent a sea monster.
A spear with three prongs.