Describes a person whose abilities are being overestimated
Person: "Hey, can you help me with my math? You seem like you know what you're doing".

Fool: "Oh no, sorry, I'm just a fool in a trench coat". I know nothing".

or

Person: "How is that person so smart? They know everything??!!!"
Grump: "Please! They're just a fool in a trench coat. They have no idea what they're doing".
by I'm really stressed out rn October 16, 2017
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