1. In conventional photography, the chemical reaction caused by allowing light rays to reach the photosensitive film for a fraction of a second. The amount of light reaching the film is determined by the camera's shutter speed and lens aperture. Overexposure or underexposure results in images that are either too light or too dark. Double exposure involves the superimposition of two images whereby a photograph is taken and the film is wound back before a second picture is taken.
2. The amount of light energy reaching a photographic film as determined by the shutter speed and lens aperture.
3. An individual's auditory and/or visual contact with a specific medium or message, or a measurement of the amount of such contact. In relation to advertising, see also effective frequency; effective reach.
4. (research) Being subjected to an experimental condition or treatment.
5. Of the body: see exhibitionism.
6. (media exposure) (public relations) The amount of media coverage a client (such as a performer or a politician) is getting, and whether this is sufficient, insufficient (under-exposure), or in danger of cheapening them as a brand (over-exposure).