Existimátor, pen. prod. rôris, m. g. Verbale mascul Cicero One that speaketh as he supposeth, & not a master or perfice iudge.Doctus & intelligens existimator.Cic.
Lewis and Short: Latin dictionary
existĭmātor (existŭm-), ōris, m. [id.], a judge of any thing, a critic (rare but class.): ut existimatores videamur loqui, non magistri, Cic. Or. 31, 112: doctus et intellegens, id. Brut. 93, 320; cf.: intellegens dicendi. id. ib. 54, 200: stultus alieni artificii, id. de Or. 3, 22, 83: non levis, Gell. 20, 1, 10: existimator metuendus (opp. admirandus orator), Cic. Brut. 39, 146.