Ritual and respect

Ajarn

อาจารย์

Also written arjan or acharn

What it means

A senior teacher, a step above kru in seniority and usually applied to the person who runs the camp or who taught the trainers.

You will not usually be the one deciding who gets the title. Listen to what the Thai staff call someone and use the same word.

Getting this right matters more in traditional camps than in large foreigner-facing ones, where first names are common.

Kru
Teacher. Used as a title before a trainer name, and the word at the centre of the sport, since the wai kru itself is a bow to the teacher.