Wikipedia
The arbelas (plural arbelai) was a type of ancient Roman gladiator. The word is a hapax legomenon, occurring only in the Oneirocritica of Artemidorus, a Greek work on dream interpretation that discusses the symbolism of various gladiator types. It may be related to the Greek word arbelos , a cobbler's semicircular blade used to cut leather similar to an ulu.
A few reliefs show gladiators armed with a curved blade fighting each other; it has been argued that these (possibly also fighting retiarii, the net-fighters) are arbelai; however, they have also been seen as the scissores who likewise may have been matched against retiarii. The scissor, with whom the arbelas may be synonymous, is referred to in a roll call from the gladiator training school ( ludus) owned in the 1st century BC by the lanista C. Salvius Capito.
Artemidorus lists the arbelas among gladiators who might appear in dreams advising a man about what sort of woman he is to marry. Both the dimachaerus, who fought with two curved blades, and the "so-called" arbelas signify that the woman will either be a poisoner, malicious, or ugly.