ionizing radiation that is naturally present in the environment.

(computing, Unix) A process that is not currently able to receive input from its controlling terminal.

plural of background process

A work or medium used (mostly) for the purpose of boosting the enjoyment of another medium.

Any music played in a public space whose main function is to create an atmosphere suitable to a specific occasion, rather than to be listened to.

Used other than figuratively or idiomatically: see low-background, steel. / Steel with low inherent radiation levels, suitable for instruments and experiments highly sensitive to radiation.

Used other than figuratively or idiomatically: see low-background, lead. / Lead with low inherent radiation levels, suitable for instruments and experiments highly sensitive to radiation.

Ellipsis of cosmic gravitational-wave background.

Alternative form of gravitational wave background

(astronomy) Faint thermal radiation that pervades all space and is thought to be the remnants of the big bang, produced during the epoch of recombination.