ashes
n. C / Un. the grey or black powder that stays behind after something has burned completely. You usually see this in a fireplace or after a campfire.
n. the solid remains of a substance that has been completely consumed by fire. Often used in the plural to refer to the cremated remains of a human body.
He cleaned the cold ashes out of the fireplace.
After the campfire died down, only a pile of glowing red embers and grey ashes remained in the pit.
The volcanic eruption blanketed the surrounding villages in a thick layer of grey ashes, choking the local vegetation and forcing a total evacuation of the valley.
Usually used in the plural form 'ashes' when referring to the residue of a fire or cremated remains; the singular 'ash' is more common in technical or volcanic contexts.