Green’s Dictionary of Slang

widow’s mite n.

[rhy. sl.]

a light, usu. for a cigarette.

[UK](con. 1914–18) Brophy & Partridge Songs and Sl. of the British Soldier.
[UK]J. Franklyn Dict. of Rhy. Sl.
[UK]Dodson & Saczek Dict. of Cockney Rhy. Sl.