noun, plural big·mouths [big-mouth z, -mouths] /ˈbɪgˌmaʊðz, -ˌmaʊθs/ for 1; (especially collectively) big·mouth, (especially referring to two or more kinds or species) big·mouths for 2.
a loud, talkative person, especially one who lacks discretion.
any of several fishes having an unusually large mouth.
blowhard, boaster, brag, braggart, gossiper, know-it-all, windbag, bragger, gasbag, grandstander, show-off, trumpeter
Origin of bigmouth
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for bigmouth
Historical Examples of bigmouth
Bigmouth buffalo were rare, and were taken only in quiet parts of larger streams, and in the borrow-pit at Station 6-S.Fishes of the Big Blue River Basin, Kansas
W. L. Minckley
slang a noisy, indiscreet, or boastful person
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012