Ring mate touring Spain (4)
I believe the answer is:
peal
'ring' is the definition.
(I know that ring can be written as peal)
'mate touring spain' is the wordplay.
'mate' becomes 'pal' (both can mean a friend).
'touring' means one lot of letters goes inside another (touring can mean going round).
'spain' becomes 'e' (abbreviation for Espana).
'pal' going around 'e' is 'PEAL'.
(Other definitions for peal that I've seen before include "Leap up to loud ring of a bell" , "Loud ringing of bells" , "Chime" , "Deep prolonged sound" , "Prolonged sound of a bell" .)