For example worker in railway plant (9)
I believe the answer is:
eglantine
'plant' is the definition.
The answer is an example.
'for example worker in railway' is the wordplay.
'for example' becomes 'eg' ('e.g.' can be a synonym of 'for example').
'worker' becomes 'ant' (worker is a type of ant).
'in' indicates putting letters inside.
'railway' becomes 'line' (line is a kind of railway).
'ant' inserted into 'line' is 'lantine'.
'eg'+'lantine'='EGLANTINE'
(Other definitions for eglantine that I've seen before include "Inelegant (anag.); wild rose" , "Inelegant sort of sweet-brier" , "Inelegant (anag) - plant" , "Sweet brier" , "Sweetbriar, inelegant in a way" .)