What is "knickerbocker glory"

n. (context UK English) An elaborately-layered ice cream sundae served in a tall glass.

A knickerbocker glory is a layered cream sundae that is served in a large tall conical glass to be eaten with a distinctive long spoon, particularly in the British Isles.

The knickerbocker glory, first described in the 1920s, may contain ice cream, cream, fruit, meringue. Layers of these different sweet tastes are alternated in a tall glass and topped with different kinds of syrup, nuts, whipped cream and often a cherry.