'autocombustion' originates from Greek and Latin, specifically the Greek prefix 'auto-' (from 'autos') meaning 'self' and the Latin word 'combustio' (from 'comburere') meaning 'to burn'.

'autocombustion' is a modern English compound formed by combining 'auto-' and 'combustion' in scientific and technical usage in the 19th–20th century; it did not exist as a single lexical item in older English but was coined from these classical elements.

Initially used in technical contexts to denote literal self-ignition of materials, the term has retained that primary sense while also occasionally being used figuratively to describe sudden, self-generated outbreaks (e.g., of emotion or controversy).