mouth off Definition

mouth
noun mouths

1a. In humans, animals, etc: an opening in the head through which food is taken in and speech or sounds emitted, and containing the teeth, gums, tongue, etc;
1b. In other creatures: an opening with similar functions.
2. The lips; the outer visible parts of the mouth.
3. An opening, eg of a bottle.

Thesaurus: orifice, opening, cavity, aperture, vent, outlet.
4. The part of a river that widens to meet the sea.

Thesaurus: estuary, delta, harbour, gateway, portal, inlet, sound.
5. A person considered as a consumer of food.

Example: five mouths to feed
6. derog, colloq
Boastful talk.
Example: He's all mouth
7. colloq
Backchat or cheek.
Example: don't want any of your mouth
8a. derog, colloq
Someone who talks too much, especially indiscreetly;
derog, colloq
Example: bigmouth
Example: loudmouth
9. colloq
Use of language; way of speaking.
Example: a foul mouth
10. The responsiveness of a horse to the bit (see bit² sense 1).

verb mouthed, mouthing

1. To form (words) without actually speaking.

Example: mouthed a hello to me across the crowded room
tr & intr
2. derog
To speak (words) pompously or insincerely.
Example: is always mouthing platitudes
intr
3. To grimace.

Derivative: mouthed

Using a specified kind of language.
Example: foul-mouthed

Having a specified kind of mouth.
Example: wide-mouthed

Idiom: be all mouth

derog, colloq
To be someone who is full of boastful or confident talk but who never actually acts upon it.

Idiom: have a big mouth

colloq
To be in the habit of talking indiscreetly, loudly or too much.

Idiom: down in the mouth

See under down¹.

Idiom: keep one's mouth shut

colloq
To keep quiet; not to say or disclose anything.

Etymology: Anglo-Saxon muth.

Phrasal Verb: mouth off

To express opinions forcefully or loudly. Also called sound off.To boast or brag.