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mouth

n. · v.
US //ˈmaʊθ// mouth
  1. 1 anatomy (n.)
    A1 Beginner Medicine

    the opening in your face that you use to eat, breathe, and speak.

    the oral cavity and its external opening, used for the ingestion of food and the articulation of sound.

    Example

    Keep your mouth closed while you are chewing your food.

    Example

    The dentist asked the patient to open her mouth wide so he could inspect the molars for signs of decay.
    • oral cavity
  2. 2 river/cave opening (n.)
    B1 Intermediate

    the place where a river enters the sea, or the entrance to a cave or tunnel.

    the point where a river issues into a larger body of water, or the entrance to a hollow structure such as a cave or valley.

    Example

    The city was built near the mouth of the river to help with trade.

    Example

    As they approached the mouth of the cavern, the temperature dropped significantly and the sound of dripping water echoed from within.
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  1. 3 talkative person (n.)
    C1 Advanced Informal Slang

    a person who talks too much or says rude things.

    a person who is excessively talkative, boastful, or prone to making tactless remarks.

    Example

    Don't listen to him; he's just a big mouth who likes to complain.

    Example

    The office mouth couldn't help but reveal the details of the confidential merger before the official announcement was made.
    • loudmouth
    • chatterbox
  2. 4 to speak silently (v.)
    B2 Upper Intermediate

    to move your lips as if you are speaking, but without making any sound.

    to form words with the lips silently, often to communicate privately or to accompany a recording.

    Example

    She mouthed the words 'thank you' from across the crowded room.

    Example

    During the performance, the backup singers were clearly mouthing the lyrics rather than actually singing into their microphones.
  3. 5 to say insincerely (v.)
    C1 Advanced Formal

    to say something without really meaning it or thinking about it.

    to utter words or ideas in a mechanical or insincere manner, often without genuine conviction.

    Example

    The politician just mouthed the same old promises during his speech.

    Example

    It was disappointing to hear the CEO simply mouth corporate platitudes instead of addressing the employees' specific concerns about job security.
Origin

From Middle English mouth, from Old English mūþ, from Proto-West Germanic munþ, from Proto-Germanic munþaz (“mouth”), from Proto-Indo-European *ment- (“to chew; jaw, mouth”). Cognate with Scots mooth (“mouth”), North Frisian mös, müs, Mür (“mouth”), West Frisian mûn (“mouth”), Dutch mond (“mouth”), muide (“river mouth”) and mui (“riptide”), German Mund (“mouth”), Luxembourgish Mond (“mouth”), Danish mund (“mouth”), Faroese muður, munnur (“mouth”), Icelandic munnur (“mouth”), Swedish mun (“mouth”), Norwegian munn (“mouth”), Gothic 𐌼𐌿𐌽𐌸𐍃 (munþs, “mouth”), Latin mentum (“chin”) and mandō (“to chew”), Ancient Greek μάσταξ (mástax, “jaws, mouth”) and μασάομαι (masáomai, “to chew”), Albanian mjekër (“chin, beard”), Welsh mant (“jawbone”), Hittite [script needed] (mēni, “chin”). The verb is from Middle English mouthen, from the noun.

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