A right pain around Ealing at first, like the bloody Tube! (8)
I believe the answer is:
arterial
'like the bloody tube' is the definition.
I can't judge whether this defines the answer.
'a right pain around ealing at first' is the wordplay.
'right' becomes 'r' (abbreviation).
'pain' becomes 'trial' (I can't justify this - if you can you should believe this answer much more).
'around' indicates putting letters inside.
'at first' suggests taking the first letters.
The first letter of 'ealing' is 'e'.
'trial' enclosing 'e' is 'terial'.
'a'+'r'+'terial'='ARTERIAL'
Can you help me to learn more?
(Other definitions for arterial that I've seen before include "Like main way" , "Main (road); of blood tube" , "on an important route?" , "Relating to major routes" , "Like certain vessels" .)