- Remaining composed and level-headed at all times; impossible to fluster; not becoming frustrated or irritated easily. [from 1954]
- 1959, The Economist, volume 190:
- The whole thing looked remarkably like an implacable force meeting an unflappable object.
- 1978, James D. Margach, The abuse of power: the war between Downing Street and the media from Lloyd George to Callaghan:
- It was for this reason that when Lord Hailsham first described Harold Macmillan as "unflappable'", it became an instant catchword, distancing the incoming Prime Minister from his predecessor
remaining composed and level-headed at all times