gabby-mouth
A 'gabby-mouth' is someone who talks nonsense and won't stop talking even when you scream at them.
My neighbor is a gabby-mouth. He talks about his garden even when I'm trying to eat dinner.
My brother is a gabby-mouth. He talks about his video games all day long.
My teacher said my class is a bunch of gabby-mouths. We talk too much even when we’re supposed to be quiet.
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