An Ordinary was a type of lecture given in universities of the Middle Ages

Middle Ages

The Middle Ages is a periodization of European history from the 5th century to the 15th century. The Middle Ages follows the fall of the Western Roman Empire in 476 and precedes the Early Modern Era. It is the middle period of a three-period division of Western history: Classic, Medieval and Modern...

. Lectures were distinguished by the time of day they were conducted: an ordinary was conducted by fully qualified professors on fundamental texts in the morning, while extraordinary lectures were given in the afternoon by bachelors (the medieval equivalent of a graduate student) on less important texts.