C / compulsor
noun

compulsor

gen. compulsōris · gender masculine · decl. 3rd
id. (late Lat.).
a driver
Lit., a driver (of cattle), Pall. Jun. 2, 3. —
one who asks; forces to a payment, an exacter of money by extension
Transf., one who asks or forces to a payment, an exacter of money, Amm. 22, 6, 1; Cod. Th. 8, 10, 3 and 4; 11, 7, 15.