The term 'beat the pants off' is an idiom that means to defeat someone or something decisively. The two crossword solutions for this term are 'ROUT' (4 letters) and 'TROMP' (5 letters). 'ROUT' is a verb meaning to force someone or something to retreat or flee in confusion, while 'TROMP' is a verb meaning to walk heavily or stomp. Therefore, both words can be used to describe a decisive victory over someone or something.