Wafter
A colleague prone to vacating their desk/seat and disappearing for extended periods to saunter and waft around in a manner akin to a fart, informally referred to as 'doing a Bernie' or 'going on a Bernie'; they may return sporadically only to promptly disappear again, in which case they shall be referred to as having completed a 'double-waft' or 'double-Bernie'. From the Latin phrase 'Whenum isum Bernum est?' meaning 'Where is the Wafter?'
'Where's John, he's been in and out of his seat like a jackrabbit all morning, and now he's been gone for two hours?'

'What do you expect of a Wafter, he must be on another marathon Bernie'