A term with two main meanings:
a mixture of flour and (usually) fat and water with (sometimes) other ingredients, made into a dough and cooked, and then used to cover, support, encase, or constitute dishes such as are described under pie, tart, pasty, and croissant; and
a particular dish which consists partly or wholly of pastry in the first sense.
(1) is dealt with here, (2) under pastries.
In this entry there are three interlocking and overlapping sections. The first gives a classification of the main types of pastry now in use. The second explains in a summary way the physics and chemistry of pastry-making. The third recapitulates briefly what is known about the history of the development of certain kinds of pastry.