I seem to remember it was a junior doctors’ mess room game to express amusement at some doctor’s surnames (Mr Butcher, the surgeon; Lord Brain the neurologist; Dr Child, the paediatrician etc). The other thought experiment related to collective nouns for groups of staff. A ‘scab’ of dermatologists; a ‘clot’ of haematologists; a callus of orthopaedic surgeons, and so on. For professors, it was simply ‘absence’— an ‘absence of professors’. The THE has wondered what the term might be for university Principals (Vice-Chancellor or Presidents). The noun is ‘lack’, as in a lack of Principals.