Definition.com
A Know-it-all is a man who never opens his mouth without subtracting from the sum of human knowledge.
Definition.com
A Know-it-all is a man whose wide range of information is always bas'ed on a narrow acquaintance with facts.
Definition.com
A Know-it-all is one who knows everything, except how to keep others from thinking him a fool.
Definition.com
A Know-it-all is one who doesn't recognize their betters because they don't acknowledge that they exist.
See also
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