Definition of "dukey"

Delicate perfumes floated through the theatre; at the penny "dukey," fried fish and hot codlins reminded you more of food than fantasy.

1919, Thomas McDonald Rendle, Swings and Roundabouts: A Yokel in London, page 50

Between the pieces were individual turns, comic songs and dances. […] Simpson, also the proprietor of a Dukey in Queen Square, Westminster, was the aristocrat of the Penny Gaffs.

1960, Theatre Notebook, volumes 14-16, page 122