Add the word BACK before the word described by the first clue to get the word described by the second clue.
-1. BACK + Antonym of down = Copy of the original
-2. BACK + Fall = Part of a stage setting
-3. BACK + To talk over the internet = Banter
-4. BACK + To lightly touch someone or something = Swimming technique
-5. BACK + Piece of wood = Pending work
-6. BACK + Nip = To talk ill of someone in their absence
7. BACK + Part of the human body = Spinal column
-8. BACK + Divisions in a hospital = Reverse direction
-9. BACK + Injure with a knife = Betray
10. BACK + Fruit of the palm tree = To bring into effect retrospectively