The passage associates the "andabata" loosely with "essedarii", chariot fighters. The word is extremely rare in classical sources, and of doubtful etymology; Delamarre suggests it as a Latinised borrowing from Gaulish. The "arbelas" as gladiator type is mentioned only in the "Oneirocritica" of Artemidorus, which discusses dream-symbols and their significance in dream interpretation. It may be related to the Greek word "arbelos" (ἄρβηλος), a cobbler's semicircular blade used to cut leather. The "bestiarius" was a beast-fighter. See also "Damnatio ad bestias". "Bustuarius" was literally a "tomb fighter," from "bustum", "tomb", a generalised reference to the association of gladiatorial combat with funeral games "(munera)". Servius notes that it had once been "the custom to put captives to death at the graves of strong men, which later seemed a bit cruel, so it was decided to have gladiators fight at the tombs." Even among gladiators, it was an unflattering term: Cicero used it to liken the morals of his enemy Clodius to those of the very lowest gladiator class. The "cestus" was a fist-fighter or boxer who wore the "cestus", a heavy-duty type of knuckleduster, but otherwise had no armour. The Roman historian Tacitus describes a Gaulish contingent of trainee, slave gladiators as "crupellarii", equipped "after the national fashion" of Gallia Lugdunensis under Julius Sacrovir, during the Aeduian revolt of AD 21 against Rome. Tacitus has them "encased in the continuous shell of iron usual in the country", labouring under its weight, unable to fight effectively, rapidly tiring and soon dispatched by regular Roman troops. Tacitus' source could refer to a heavily armoured Roman "Gallus" type, which by Tacitus' own time had been developed and renamed as the Murmillo. The "dimachaerus" (Greek διμάχαιρος, "bearing two knives") used a sword in each hand. "Eques", plural "equites", was the regular Latin word for a horseman or cavalryman. Early forms of the "eques" gladiator were lightly armed, with sword or spear.