petasio

pĕtăsĭo and pĕtăso, ōnis, m., = petasôn, a leg or pestle of pork, esp. the shoulder (opp. perna, the ham):

e Galliā apportantur Romam pernae tomacinae et taniacae, et petasiones,

Varr. R. R. 2, 4, 10:

pulpam dubio de petasone voras,

i. e. that has already begun to turn, Mart. 3, 77, 6.