General terms:
* Reuse: This is the most common and general term.
* Recycle: This refers specifically to processing used materials into new products.
* Repurpose: This means finding a new use for something that's no longer needed for its original purpose.
* Re-utilize: A more formal way of saying reuse.
* Reapply: Used when you apply something again, like paint or a bandage.
* Reactivate: Used when you bring something back into operation after it was inactive.
More specific terms:
* Re-wear: Used for clothing.
* Re-read: Used for books.
* Refill: Used for containers that can be filled again.
* Re-use: This is a more colloquial version of reuse.
The best word to use will depend on the specific situation.