(nuclear physics) An accidental uncontrolled self-sustaining nuclear fission chain reaction.

(informal) To urinate or defecate somewhere other than a toilet. / Used other than figuratively or idiomatically: see have, accident.

The continuous and roughly simultaneous surge in growth rate across a large range of measures of human activity, first recorded in the mid-20th century.

(automotive, of electrified vehicles) The standard 12V rechargeable automotive lead-acid battery or the stand-in battery for a standard 12V automotive battery found in internal combustion engined vehicles, typically used to power the typical 12V systems, the accessories, infotainment, automotive computer, and electronic systems.