Simple creature, European, amongst crowd accepted by drivers’ club (6)
I believe the answer is:
amoeba
'simple creature' is the definition.
(I've seen this in another clue)
'european amongst crowd accepted by drivers' club' is the wordplay.
'european' becomes 'E' (abbreviation e.g. EU).
'amongst' means one lot of letters goes inside another (I've seen this in other clues).
'crowd' becomes 'mob' (mob can mean a crowd of people).
'accepted by' is an insertion indicator.
'drivers' club' becomes 'aa' (I can't justify this - if you can you should believe this answer much more).
'e' put into 'mob' is 'moeb'.
'moeb' going inside 'aa' is 'AMOEBA'.
Can you help me to learn more?
(Other definitions for amoeba that I've seen before include "Simple creature" , "Microscopic animal found in water" , "Microscopic creature found in water" , "little creature" , "Single-celled animal" .)