Prat
Part of speech: adjective
Definition: cunning, astute
Part of speech: noun
Definition: The buttocks. A fool. The female genitals.
Arse
Part of speech: noun
Definition: (not used in US, Canada) buttocks; the back of anything.(not used in US, Canada) stupid, mean or despicable person.
Part of speech: verb
Definition: To be silly, act stupid or mess around.To have the effort to do something, to be bothered.
Example sentence: Young people can be disruptive and screw up classes. But even if they are being a pain in the arse it's a cry for help - they don't feel like they are being listened to.