A word search, word find, word seek, word sleuth or mystery word puzzle is a word game that consists of the letters of words placed in a grid, which usually has a rectangular or square shape. The objective of this puzzle is to find and mark all the words hidden inside the box. The words may be placed horizontally, vertically, or diagonally. Often a list of the hidden words is provided, but more challenging puzzles may let the player figure them out. Many word search puzzles have a theme to which all the hidden words are related. The puzzles have, like crosswords and arrowords, been very popular in the United Kingdom, and - also in common with these latter puzzles - have had complete magazines devoted to them.
Word searches are commonly found in daily newspapers and puzzle books. Some teachers use them as educational tools for children, the benefit being that young minds can learn new words and their spellings by intensively searching for them, letter by letter, in the puzzle.