Formerly, the last of the three meals of the day (breakfast, dinner, and supper); now applied to the last substantial meal of the day when dinner is taken in the middle of the day, or to a late meal following an early evening dinner. Supper is usually a less formal meal than late dinner.
My guess would be food after a late work shift, so probably working class
https://www.etymonline.com/word/supper
My guess would be food after a late work shift, so probably working class
if you call dinner the main meal of the day, the earlier you start work, the earlier you’ll have it