Lewis & Short

1. blătĕro, āvi, ātum, 1, v. a. [kindred with βλάξ, simple, stupid, Paul. ex Fest. p. 34 Müll.; cf. blactero].

  1. I. To talk idly or foolishly, to babble, prate (colloq. and mostly ante- and post-class.), Pac. ap. Fulg. p. 561, 17; Afran. ap. Non. p. 78, 32: illud memento, ne quid in primis blateres, id. ib.; Plaut. ap. Non. p. 44, 15: desine blaterare, Caecil. ap. Non. p. 79, 2: cum magno blateras clamore, furisque, * Hor. S. 2, 7, 35; Gell. 1, 15, 17: his et similibus blateratis, App. M. 4, p. 153, 18; so id. Mag. p. 275, 8; id. Flor. p. 345, 19.
  2. II. Of the sounds of frogs, Siā Ep. 2, 2 med.; and of camels, acc. to Paul. ex Fest. p. 34, 2 Müll.