Professor (informally also known as full professor) is the highest academic rank at universities and other institutions of higher education in parts of the world. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of the highest rank.
In most Commonwealth nations (such as the United Kingdom, Australia, New Zealand, South Africa, English-speaking Caribbean) and northern Europe, professor is the title of the most senior academics at a university. It may come with the additional honor of being an endowed professorship. A professor is a highly accomplished and recognized academic, and the title is in most cases awarded only after decades of scholarly work to senior academics.
The word professor is also used in other, lower titles such as Assistant Professor and Associate Professor, particularly in United States and Canada. Professor is the North American equivalent of Professor in other countries and uniquely signifies that the academic has been awarded tenure.