Prefix uni-

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Across
  1. 2. one group
  2. 4. a group that acts like one
  3. 5. to join together
  4. 6. moving in one direction
  5. 7. having only one cell
Down
  1. 1. a fable animal with one horn
  2. 2. a one wheeled vehicle
  3. 3. one of a kind
  4. 5. a one piece leotard and tights combination
  5. 8. one sided