A first aid technique to return an unconscious person's respiration by pressing the rescuer's mouth against the mouth of the patient and blowing air into his/her lungs.

plural of mouth-to-mouth resuscitation

(genetics, biochemistry) A receptor-like protein in plants which, when absent, leads to an overproduction of stomata

From the comments of children, who are honest and innocent, . . . (comes truth or wisdom).

(obsolete) Talkative; eager to speak. / With the mouth open. / Gaping in surprise, wonder or astonishment.

(intransitive, slang) To complain or otherwise express oneself in a loud, immoderate manner. / (transitive, intransitive, slang) To talk impudently, especially to one's superior.

simple past tense and past participle of mouth off

present participle of mouth off

(informal) Regularly using vulgar language, especially strong profanities.

(idiomatic, euphemistic) The characteristic of regularly using vulgar language, especially strong profanities. / (idiomatic) A person having this characteristic.