student teacher
/ˌstjuːdn(t) ˈtiːtʃə/ /ˌstʃjuːdn(t) ˈtiːtʃə/noun
A student who is training to be a teacher, typically one who spends a specified period teaching in a school as a part of a formal teaching qualification.
Origin
Mid 19th century; earliest use found in The Lancet. From student + teacher.