Lewis & Short

hărĭŏlor (ar-), āri, v. dep. n. [hariolus], to foretell, prophesy, divine.

  1. I. Lit.: Προθεσπίζω igitur, non hariolans, ut illa (Cassandra) cui nemo credidit, sed conjectura prospiciens, Cic. Att. 8, 11, 3: quaestus causa hariolari, id. Div. 1, 58, 132.
    Comically: mirabar, quod dudum scapulae gestibant mihi, Hariolari quae occeperunt sibi esse in mundo malum, Plaut. As. 2, 2, 50.
  2. II. Transf., in a bad sense (like vaticinor), to speak foolishly, to talk silly stuff, nonsense (ante-class.), Plaut. Cist. 4, 2, 80; id. As. 3, 2, 33; 5, 2, 74; id. Rud. 2, 3, 17; Ter. Phorm. 3, 2, 7; cf. Plaut. Rud. 4, 4, 97: age jam cupio, si modo argentum reddat. Sed ego hoc hariolor, am dreaming, Ter. Ad. 2, 1, 48.