Lewis & Short

sermuncŭlus, i, m. dim. [sermo].

  1. I. (Acc. to sermo, I. B. 3.) Common talk, tittletattle, report, rumor (rare but class.): urbani sermunculi, Cic. Deiot. 12, 33: sermunculis fabellisque duci, Plin. Ep. 5, 8, 4: sermunculum omnem aut restinxerit aut sedarit, Cic. Att. 13, 10, 3: non deterreor sermunculis istorum, Plin. Ep. 7, 17, 14.
  2. II. A little discourse (late Lat.), Hier. Ep. 32, 1.