/big"mowth'/ , n. , pl. bigmouths /-mowdhz', -mowths'/ for 1; ( esp. collectively ) bigmouth , ( esp. referring to two or more kinds or species ) bigmouths for 2.
1. a loud, talkative person, esp. one who lacks discretion.
2. any of several fishes having an unusually large mouth.
[ 1885-90, Amer.; BIG 1 + MOUTH ]