The Spanish ambassador heads list (4)
I believe the answer is:
heel
'list' is the definition.
(I've seen this before)
'the spanish ambassador heads' is the wordplay.
'the spanish' becomes 'el' ('the' in Spanish).
'ambassador' becomes 'he' (His or Her Excellency).
'heads' is a charade indicator (letters next to each other) (some letters go ahead of others).
'el' put after 'he' is 'HEEL'.
(Other definitions for heel that I've seen before include "Back of 15 across" , "A cad and a bounder!" , "See 21" , "Come here, Rover!" , "horrible person" .)