Roger Woodham replies:Teacher/trainer/instructor/lecturer

Teacher

 
Teacher is the general term for someone whose job it is to teach:
 
I'd like to go into teaching and get a job as a teacher in an inner city primary or secondary school.
 
Teaching assistants can only ever support the classroom teacher; they can never replace him.
 

 
Tutor
 
 We sometimes use the word tutor instead of teacher to describe somebody who gives personal or private lessons:
 
My son wasn't making much progress in school, so I hired a maths tutor to give him private lessons after school.
 
If you are enrolled as a student in a British university, you will have a personal tutor who provides you with close support throughout your studies and with whom you will have tutorials to discuss aspects of the subject being studied:
 
There are just six students in my tutorial group and we had a very interesting tutorial on global warming and climate change last week. On all quality distance learning schemes, face-to-face support from trained tutors is essential.
 

 
Lecturer
 
 A lecturer is someone who gives a lecture or formal presentation, particularly at a college or university
 
Dr Gradgrind is our lecturer on the Victorian novel and the course will be taught through a series of lectures and seminars.
 

 
Note that a seminar at a college or university is a class for a small group of students to discuss the subject with the lecturer.
 

 
Professor
 
 In the UK, professor is a university teacher of the highest rank in a subject area:
 
Professor Stephen Hawking, Lucasian Professor of Mathematics at the University of Cambridge, is one of the most formidable intellects ever to theorise on the origins of the universe.
 

 
The first step in an academic carrier is usually lecturer, then senior lecturer, then reader, then eventually perhaps professor.
 
Note that in the US, a professor is a full-time teacher at university. A teacher at secondary school or high school or junior college is never a professor.
 

 
Instructor
 
 In British English, an instructor teaches you on how to learn or improve in a particular skill or sport:
 
If you want to learn how to drive, you will need a driving instructor.
 
If you want to learn how to fly, you will require a flying instructor.
 
If you intend to ski this winter on the higher slopes, you'll need a ski instructor.
 

 
In the US, an instructor is a university teacher below the rank of assistant professor.
 

 
Coach
 
 A coach is someone who trains individual sports players or a team. The examples below are taken from tennis and football:
 
Tim Henman, Britain's No 1, has a new coach, Paul Anacone, who worked with Pete Sampras for six years.
 
Paul Bracewell, national coach with the England youth teams for the past two years, has resigned.
 

 
Trainer
 
 A trainer can be someone who trains people for a particular job or profession or who trains someone in certain varieties of sport.
 
In-service teacher trainers are in very great demand here as there is no pre-service training for teachers.
 
If you can get Kevin as your personal fitness trainer, you'll work on a wide range of strategies and techniques.