This is the 8366th most frequent Spanish word.
profesor
A teacher or professor.
In this sentence, 'profesor' refers to a school teacher.
El profesor enseña matemáticas en la escuela.
The teacher teaches mathematics at the school.
Here, 'profesor' is used to refer to someone responsible for evaluating student work.
El profesor está revisando los exámenes de sus alumnos.
The teacher is reviewing the exams of his students.
In this context, 'profesor' indicates a knowledgeable person invited to share expertise, possibly in an academic setting.