A pastry case (shell) filled, before or after baking, with savoury or sweet ingredients. [...] The American term often used is open pie.
The French have adopted the English word for the classic British and American pies. A pie consists of a filling topped with a crust and baked. Pastry is the usual crust, and the filling can be savoury or sweet. [...]
Confusion often arises over the terms pie and tart. Traditionally, the British pie is made in a deep dish and has a pastry lid but not a pastry base. The traditional pie dish has a wide rim on which to place a strip of pastry to which the top crust can be attached once the filling is in place. [...]
A British tart is shallow, baked on a tart plate which is deeper than a standard dinner plate with a pastry base and a lid. [...] American pies can have a bottom crust but no lid, and the would generally be known as tarts in Britain.
anything could be served with ice cream (which is, after all, only a frozen whipped custard that can be flavored any way you like) and b) this would define ice cream as a pie, since ice cream is often served with different ice cream (or, if you reject that as recursive, a banana could be a pie...).
The words 'tart' (tarte) and 'flan' are often used interchangeably in Britain and France to designate a pastry filled with fruit, jam, custard or some other filling.
An open tart filled with fruit, a cream or a savoury mixture. [...]
The word flan is also used in France and Spain for an egg custard, often caramel-falvoured, that is made in a mould, turned out and served cold.
[Occurs (in Latin context) in 1303; evidently a well-known popular word in 1362. No related word known outside Eng.