The word rector ("ruler", from the Latin regere and rector meaning "ruler" in Latin) has a number of different meanings; it is widely used to refer to an academic, religious or political administrator.

The term and office of a rector are called a rectorate.

The rector is the highest academic official of many universities and in certain other institutions of higher education, as well as even in some secondary-level schools.

The title is used widely in universities across Europe. It is also very common in Latin American countries. It is also used in Russia, Pakistan, the Philippines, Indonesia and Israel, all of which are strongly influenced by European traditions. In some universities, the title is phrased in an even loftier manner, as Rector Magnificus or Lord Rector.

A notable exception to this terminology is in England and elsewhere in Great Britain, where the head of a university has traditionally been referred to as a "Chancellor". This pattern has been followed in the Commonwealth, the United States, and other countries under British influence. In Scotland, many universities are headed by a Chancellor, with the Lord Rector designated as an elected representative of students at the head of the university court.