Synonyms for Arse Around (same or very similar meaning)
WordNet sense 1 (be lazy or idle):
bum, loaf, loll, arse about, bum about, bum around, frig around, loll around, lounge about, lounge around, waste one's time, fuck offWordNet sense 2 (indulge in horseplay):
fool, horse around, fool aroundFrom the ODE community, based on WordNetadd/edit