The Collaborative International Dictionary of English v.0.48:
Vociferous \Vo*cif"er*ous\, a. [Cf. F. vocif[`e]re.] Making a loud outcry; clamorous; noisy; as, vociferous heralds. -- Vo*cif"er*ous*ly, adv. -- Vo*cif"er*ous*ness, n. [1913 Webster]WordNet (r) 3.0 (2006):
vociferously adv 1: in a vociferous manner; "he complained vociferously"