What is "murmillo"

The murmillo (also sometimes spelled mirmillo or myrmillo, pl. murmillones) was a type of gladiator during the Roman Imperial age. The murmillo-class gladiator was adopted in the early Imperial period to replace the earlier Gallus, named after the warriors of Gaul. As the Gauls inhabiting Italy had become well-integrated with the Romans by the time of the reign of Augustus, it became undesirable to portray them as enemy outsiders; the Gallus-class gladiator thus had to be retired.