주둥이

(slang) The human mouth.

The protruded part around an animal's nose or mouth.

The long, narrow part of a bottle, container, etc., through which the substance inside is released.

주둥이가 가볍다[싸다]

(slang) To tend to leak someone's secret.

(disparaging) To talk in a careless manner.

(slang) To talk back to someone in an impolite manner.

(disparaging) To talk about something in a plausible manner, but never put it into action.