What do you call it when you kill 159,000 turkeys after an outbreak of bird flu? You use the highly euphemistic term ‘cull’. Oddly, ‘cull’ originally meant to select things you want to keep (culling strawberries, culling quotations), but eventually reversed emphasis. A 1964 book on Uganda’s national parks notes: ‘The experimental shooting of hippo – culling is the polite conservation term for it – had begun.’