n. A type of gladiator, who uses a casting net (a rete or iaculum) as a weapon.
the GNU version of the Collaborative International Dictionary of English
n. A gladiator armed with a net for entangling his adversary and a trident for despatching him.
The Century Dictionary and Cyclopedia
n. In Roman antiquity, a gladiator who wore only a short tunic and carried a trident and a net.
Word Usage
"With a movement unbelievably swift King was there ahead of him; and with another movement not so swift, but much more disconcerting, he threw his sheet as the retiarius used to throw a net in ancient Rome."