When he called you a know-it-all, he meant it as a put-down.
An example of a put-down is to call someone ugly.
Finally she put down her fork and gave up the pretense.
I put down my knife to join her.
The kitchen clock ticked off thirty seconds before she put down her fork and pushed away from the table.
She put down the last plate and turned around to see what he was doing.
Fred sighed and put down the newspaper.