We received a 'tax refund' this year. [=this year we paid too much income tax so we got some money back]
They refused to 'refund' the ticket. [=to give back the money that I had paid for the ticket]
If you are not completely satisfied, we will 'refund' the purchase price.
(..) I found your man. He's buried in Blackwood's tomb. If you still need him. Oh dear... I hope my client doesn't come looking for a refund. He's a professor, isn't he? I couldn't see his face, but I spotted a bit of chalk on his tappan. I've never known a professor to carry a (..)2009 Sherlock Holmes