Refund is a term that means the act of get the money backo borrowed or spent on a service or product that was not properly used or offered.
When an individual or institution receive a refund it means that you are getting back an investment that was made for a certain objective that was not fulfilled, consequently getting back the money that was spent in the past.
Mandatorily, when a company offers a certain service to its customers and does not fulfill its responsibilities or pre-established basic conditions must offer consumers the option of reimbursement, that is, partial or total return of the cash. Example: "The cinema had to reimburse all people who could not watch the film due to the problem in the screening room.".
Commonly, people tend to request the reimbursement of expenses when, in specific situations, they need to spend money buying products or services for the benefit of a third person. An example is when someone travels on a work mission. Example: "Joana asked for a full refund of the nights she paid at the hotel during the company meeting".
In the mail delivery service, such as the post office, for example, there is the Postal Refund, which consists of a service modality for sending goods where the sender stipulates a value to be charged to the recipient so that he can have the right to withdraw the order from the distribution agencies of the post offices.
In English, the word "refund" can be translated to reimbursement or refund.