substitute teacher
noun /ˌsʌbstɪtjuːt ˈtiːtʃə(r)/
/ˌsʌbstɪtuːt ˈtiːtʃər/
(also informal sub)
(both North American English) (British English supply teacher)
- a teacher employed to do the work of another teacher who is away because of illness, etc.
代课教师