tickler

noun

1. One who tickles.
2. A person who or thing which amuses or excites.
3. A reminder.
4. A latex condom that has additional protrusions, for enhancing the sexual pleasure of the user.
5. Something puzzling or difficult; a conundrum.
6. A tickler file, file cabinet, or similar containing memoranda of deadlines arranged in date order.
7. A prong used by coopers to extract bungs from casks.
8. A dram of spirits.
9. Something puzzling; a poser.
10. A small notebook that fits the pocket or pocket notebook.