English celebrity describing our fantastic rail service (8)
I believe the answer is:
eurostar
'rail service' is the definition.
(I've seen this before)
'english celebrity describing our fantastic' is the wordplay.
'english' becomes 'e' (abbreviation).
'celebrity' becomes 'star' (I've seen this before).
'describing' means one lot of letters goes inside another (describe can mean to form the outline of).
'fantastic' is an anagram indicator.
'e'+'star'='estar'
'our' anagrammed gives 'uro'.
'estar' placed around 'uro' is 'EUROSTAR'.
(Other definitions for eurostar that I've seen before include "High-speed rail link between the UK and France" , "Railway service via the Channel Tunnel" , "International traveller" , "The train from England to France" , "Service from St Pancras" .)