psychologist vs school counselor

psychologist

noun
  • An expert in the field of psychology. 

school counselor

noun
  • A professional member of an educational team who assists students in their personal, social, academic, and career development aspects of education through services such as individual counseling, small group counseling, and classroom teaching, and provide leadership in educational reform (advocacy); traditionally known as a guidance counselor, although this term is deemed inaccurate by most professionals today. 

How often have the words psychologist and school counselor occurred in a corpus of books? (source: Google Ngram Viewer )