fly ash

fly ash (uncountable)

1. A residue generated in combustion, comprising the fine particles that rise with the flue gases, and used in construction materials.
   • 1964 August, “BR in 1963 - "we have turned the financial corner"”, in Modern Railways, page 115:

     Among new freight vehicles was a prototype 21-ton wagon with pressure discharge for the conveyance of fly ash from power stations, [...]

   • 2022 September 7, Gareth David, “Class 20 stronghold in the Peak District”, in RAIL, number 965, page 45:

     "Besides our sending out of cement by rail, we also bring in pulverised fly-ash, typically once a week, which comes from Drax Power Station and is used in the cement manufacturing process," adds Hodgson.

• “fly ash”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.

• flashy