Tending to use obscene or offensive language.

simple past tense and past participle of bad-mouth

Having a broad mouth. / (obsolete) Outspoken; rude.

Alternative spelling of bigmouthed

(idiomatic) (in a positive sense) Having a sweet and smooth voice; eloquent.

Smooth and persuasive in speech, especially in order to deceive or manipulate. / Unclear, muffled, or halting in speech.

Using foul or scurrilous language; slanderous.

Not sensitive to the bit; not easily governed. / Hard-featured about the mouth.

Expanding at the mouth.

(obsolete) Having a projecting under jaw; prognathous.