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bigmouthed

[big-moutht, -mouthd] / ˈbɪgˌmaʊθt, -ˌmaʊðd /
ADJECTIVE
blabby
Synonyms
WEAK
chattery chatty newsy taletelling talkative
ADJECTIVE
loudmouthed
Synonyms
WEAK
bellowing big-voiced blustering boisterous full-throated obnoxious vociferous
ADJECTIVE
voluble
Synonyms
STRONGEST
chatty loquacious
WEAK
articulate chattering fluent full of hot air gabby garrulous long-winded mouthy multiloquent prolix rambling running on slick smooth talky verbal windy wordy
Antonyms
STRONGEST
quiet silent

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.