pillĕŏlus, i, m., and pillĕŏlum, i, n. dim. [pilleus],
a small felt cap , a skull-cap : ut cum pilleolo (portes) soleas conviva tribulis, Hor. Ep. 1, 13, 15; Col. Arbor. 25; Hier. Ep. 85, n. 6; 64, n. 13.
pilleolus (not pīle-), ī, m dim.pilleus, a small felt cap, skull-cap , H. ...
An Elementary Latin Dictionary