It is a term used to describe a brief speech that outlines an idea for a product, service, or project. The name comes from the idea that the speech should be delivered in the short time offered by an elevator ride. A good rule of thumb is that an elevator pitch should be ideally 30 seconds long (and a maximum of 60 seconds).
In the financial world, it represents an entrepreneur's attempt to convince a venture capitalist that a business idea is worth investing in. If successful, the pitch will be enough to get the investor interested and set up a follow-up meeting, where the entrepreneur will present the investor with a more formal & detailed presentation.