thumbtack: Meaning and Definition of

thumb•tack

Pronunciation: (thum'tak"), [key]
— n.
  1. a tack with a large, flat head, designed to be thrust into a board or other fairly soft object or surface by the pressure of the thumb.
—v.t.
  1. to attach or tack by means of a thumbtack.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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