tickler

from WordNet (r) 3.0 (2006)

tickler
    n 1: a file of memoranda or notices that remind of things to be
         done [syn: {tickler}, {tickler file}]

from The Collaborative International Dictionary of English v.0.48

Tickler \Tic"kler\, n.
   1. One who, or that which, tickles.
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   2. Something puzzling or difficult.
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   3. A book containing a memorandum of notes and debts arranged
      in the order of their maturity. [Com. Cant, U. S.]
      --Bartlett.
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   4. A prong used by coopers to extract bungs from casks.
      [Eng.]
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