If you
sweep something
under the rug, you try to hide it and forget about it because it makes you feel embarrassed or ashamed.
Executives swept the theft under the rug, hoping to avoid being accused of mismanagement by directors and shareholders. Some of the most appalling crimes went unpunished, swept under the rug in order to placate the military. Note: Other verbs such as
brush and
push are sometimes used instead of
sweep.
You can't just brush this one under the rug. Note: The usual British expression is
sweep something
under the carpet.