Railways tea? (4)
I believe the answer is:
brew
'tea?' is the definition.
(I've seen this before)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for brew that I've seen before include "Ferment rather than distil" , "Ferment, concoct" , "Steep" , "Infuse" , "Infusion" .)