Maître vs. professeur vs. enseignant vs. instituteur vs. prof

The French language has a number of terms that refer to the role of a 'teacher', including 'maître', 'professeur', 'enseignant', 'instituteur' and 'prof'. These words, although similar in meaning, are used in different contexts and denote different specificities of the teaching profession.

Maître

The term 'maître' literally translates to 'master' and is traditionally used for a teacher in elementary education. It is also used in a respectful way to address a teacher.
Je suis le maître de cette classe.
(I am the teacher of this class.)
Pierre est mon maître à l'école.
(Pierre is my teacher at school.)

Professeur

'Professeur' generally refers to high school teachers or university professors.
Mon professeur de mathématiques est très strict.
(My math teacher is very strict.)
Le professeur Dupont enseigne à l'université.
(Professor Dupont teaches at the university.)

Enseignant

'Enseignant' is a generic term for anyone who teaches, regardless of the level of education.
Il est enseignant de français au lycée.
(He is a French teacher at the high school.)
Elle est une enseignante dévouée dans son métier.
(She is a dedicated teacher in her profession.)

Instituteur

'Instituteur' is a somewhat old-fashioned term, historically used for elementary school teachers. Now it has been largely replaced by 'enseignant' or 'maître'.
Mon grand-père était instituteur dans un petit village.
(My grandfather was a schoolteacher in a little village.)
L'instituteur enseigne à ses élèves comment lire et écrire.
(The schoolteacher teaches his students how to read and write.)

Prof

'Prof' is an informal and abbreviated way to say 'professeur'. It's widely used among students when referring to their teachers.
Mon prof de sport est malade aujourd'hui.
(My sports teacher is sick today.)
Je vais demander de l'aide à mon prof de français.
(I will ask for help from my French teacher.)

Summary

Although all these words relate to teaching, they are used in different contexts. 'Maître' usually refers to a primary school teacher or a respectful title for a teacher, while 'professeur' often refers to a university teacher or professor. In contrast, 'enseignant' is a more general term that can be used for any teacher. 'Instituteur' used to refer to primary school teachers, but it's less common now, and 'prof' is an informal abbreviation for both students and adults.