The verbs lend and loan are interchangeable.
- Lend me 50 dollars. OR Loan me 50 dollars.
Use loan when speaking of money and use lend when speaking of objects.
- Will you lend me your camera for a day?
- Could you loan me thousand dollars until Friday?
- The bank loaned him $1000 to start a business.
- He refused to lend me his land mower.
However, note that the distinction between lend and loan is a fine one. Actually both words can be used interchangeably and there is nothing wrong with the sentence ‘He refused to loan me his land mower’.