Right on, Faldage.

There is a word "blatter" [derived from the same "blaterare" Latin root] which means pretty much the same thing as "deblaterate" [spelled with one "t"].

Dictionary.com blatter

\Blat"ter\, v. i. [imp. & p. p. Blattered.] [L. blaterare to babble: cf. F. blat['e]rer to bleat.] To prate; to babble; to rail; to make a senseless noise; to patter. [Archaic] ``The rain blattered.'' --Jeffrey.

They procured . . . preachers to blatter against me, . . . so that they had place and time to belie me shamefully. --Latimer.