THESAURUS
speak up
affirm, affront, allege, announce, annunciate, appear, argue, assert, assever, asseverate, aver, avouch, avow, beard, bell the cat, bite the bullet, brave, brazen, brazen out, break silence, come forth, confront, contend, declare, enunciate, express, face, face the music, face up, face up to, front, have, have no secrets, hold, insist, issue a manifesto, lay down, maintain, manifesto, materialize, meet, meet boldly, meet head-on, open up, pipe up, predicate, proclaim, profess, pronounce, protest, put, put it, run the gauntlet, say, say out, set at defiance, set down, speak, speak out, stand for, stand on, stand up to, state, submit, take a stand, take the floor
ROGET THESAURUS
speak up
Loudness
VB
be loud, peal, swell, clang, boom, thunder, blare, fulminate, roar, resound,
speak up, shout, bellow, rend the air, rend the skies, fill the air, din in the ear, ring in the ear, thunder in the ear, pierce the ears, split the ears, rend the ears, split the head, deafen, stun, faire le diable a quatre, make one's windows shake, rattle the windows, awaken the echoes, startle the echoes, wake the dead.