piss about

piss around

verb (adverb) slang

(intr) to behave in a casual or silly way
(tr) to waste the time of

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012