This conception of the Middle Ages is largely inaccurate, however. The Medieval period saw the founding of the first universities in Europe as well as the construction of impressive cathedrals such as the Notre-Dame of Paris. A number of scientific inventions, such as eyeglasses and mechanical clocks, improved everyday life considerably during this time. The use of heavy ploughs, horse collars, and water mills also increased agricultural productivity. There was no paucity of literary genius, either; many poetic masterpieces, such as Chaucer's Canterbury Tales and Dante's Divine Comedy, were written during the Middle Ages. Perhaps we should think twice, then, before using the term "Middle Ages" pejoratively to describe anything that is perceived as backwards, unsophisticated, or ignorant.
What is the meaning of pejoratively as used in the passage?