grassātor (noun M) : id..
* A vagabond, idler: poëticae artis honos non erat. Si qui in ea re studebat, aut sese ad convivia applicabat, grassator vocabatur, Cato ap. Gell. 11, 2, 5.
* A disorderly person, one who goes rioting about (esp. at night, whether for fun and enjoyment or for robbery), a rioter, a waylayer, street-robber, footpad: hoc modo viator quoque bene vestitus causa grassatori fuisse dicetur, cur ab eo spoliaretur,Cic. Fat. 15, 34: grassatorum plurimi palam se ferebant succincti ferro,Suet. Aug. 32: grassatores et sicarii,id. Caes. 72: nocturni grassatoris insidiosa violentia,Gell. 20, 1, 8; Quint. 12, 1, 38: ferro subitus grassator agit rem,Juv. 3, 305.

s. TLL