<Tr> <Th> Related jobs </Th> <Td> Teacher, lecturer, reader, researcher </Td> </Tr> <P> Professor (commonly abbreviated as Prof .) is an academic rank at universities and other post-secondary education and research institutions in most countries . Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences, a teacher of the highest rank . </P> <P> In most systems of academic ranks the word "professor", and particularly the unqualified word, only refers to the most senior academic position, sometimes informally known as "full professor". In some countries or institutions, the word professor is also used in titles of lower ranks such as associate professor and assistant professor; this is particularly the case in the United States, where the word professor is sometimes used colloquially to refer to anyone in an academic post . This colloquial usage would be considered incorrect nearly everywhere else . </P> <P> Professors conduct original research and commonly teach undergraduate, professional and postgraduate courses in their fields of expertise . In universities with graduate schools, professors may mentor and supervise graduate students conducting research for a thesis or dissertation . In many universities,' full professors' take on senior managerial roles, leading departments, research teams and institutes, and filling roles such as President, Principal or Vice-Chancellor . The role of professor may be more public facing than that of more junior staff, and professors are expected to be national or international leaders in their field of expertise . </P>

When do you call a teacher a professor
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