jigsaw puzzle

noun2

1. •
   A type of puzzle in which the aim is to reconstruct a picture that has been cut (originally, with a jigsaw) into many small interlocking pieces.
2. •
   An alphabetical jigsaw; a crossword in which the clues are not numbered and the solver must work out where each solution fits in the grid.

   • The grid is designed so as to make this a genuine challenge: there are six words each of four to nine letters, and nothing longer – normally it’s the long lights that are the key to a jigsaw puzzle. — 2002