A short form of "rehabilitation" or "rehab".

पुनर्वास

English Usage: After the accident, he went to rehab to recover.

Hindi Usage: दुर्घटना के बाद, वह पुनर्वास में गया।

A slang term often used in casual conversation like "stay" or "remain".

रहना

English Usage: Just reh there and I'll be back soon.

Hindi Usage: बस वहाँ रहो, मैं जल्दी वापस आऊंगा।