This word has two meanings. Firstly it is an Indian and English word for a light meal eaten during the day, or a between meals snack.
Of greater interest to us, however, is the other meaning: A cake with a base made of crushed biscuits (usually digestives) and raisins, and a chocolate topping.
Recipes vary widely and may use other biscuits (e.g. rich tea.) or perhaps omit the raisins.