to break or break something into very small pieces

if a building or piece of land is crumbling, parts of it are breaking off

The cliff is gradually crumbling away.

They live in a crumbling old mansion.

to begin to fail or get weaker or to come to an end

All his hopes began to crumble away.

The empire finally crumbled into dust.

a dessert (= a sweet dish) made from fruit that is covered with a rough mixture of flour, butter and sugar, cooked in the oven and usually served hot

LEARNit Dictionary