Letter in verse that hurt the Spanish (5)
I believe the answer is:
vowel
'letter' is the definition.
(I know that vowel is a type of letter)
'verse that hurt the spanish' is the wordplay.
'verse' becomes 'v'.
'that hurt' becomes 'ow' (exclamation of pain).
'the spanish' becomes 'el' ('the' in Spanish).
'v'+'ow'+'el'='VOWEL'
'in' acts as a link.
(Other definitions for vowel that I've seen before include "Type of letter such as A" , "Kind of letter of the alphabet" , "Possibly a" , "Non-consonant" , "Letter such as i or u" .)