To eat up completely; to finish off (food) without leaving anything.
子どもたちはピザをあっという間に平らげた。
The children devoured the pizza in no time.
彼は出された料理を一皿残らず平らげた。
He cleared every dish that was served to him.
To put down or subjugate (a rebellion); to suppress. Can be used figuratively for suppressing opposition.
政府は武力で反乱を平らげた。
The government crushed the rebellion by force.
彼は会議での反対意見をうまく平らげた。
He skillfully silenced the opposing opinions at the meeting.
To make flat; to level out (archaic usage).
古い文献には畑を平らげるといった表現が見られる。
In old texts one finds expressions like 'to level the fields.'