This puzzle contains 24 vocabulary words from the Motion in 1 and 2 Dimensions Physics units. Students work in pairs to match the vocabulary word with the definition. The completed puzzle is a 4X4 square, where all of the vocabulary words and definitions match horizontally across each row and vertically down each column. Use as a review of recently learned vocabulary, or as part of a review for your exams. You can also use this puzzle with students who have finished their work early, and need something to work on. A companion puzzle to Physics: Motion Vocabulary (Easiest) and Physics: Motion Vocabulary (Medium), this puzzle is the third in a series of 3 puzzles that are the same, but vary in difficulty. This puzzle is geared toward the advanced Physics student, and students who really enjoy a challenge.