Lewis & Short

pŭgĭuncŭlus, i, m. dim. [pugio], a small dagger or poniard (Ciceronian), Cic. Or. 67, 225.
Transf.: ille Hispaniensis pugiunculus, i. e. Cn. Piso, who had been despatched to Spain, Cic. ap. C. Anton. Fragm. ap. Ascon.