Old coin located beside Scottish island claimed by the Spanish academic (11)
I believe the answer is:
educational
'academic' is the definition.
(I've seen this before)
'old coin located beside scottish island claimed by the spanish' is the wordplay.
'old coin' becomes 'ducat' (I've seen this before).
'located beside' is a charade indicator (letters next to each other).
'scottish island' becomes 'iona' (island of the Hebrides).
'claimed by' indicates putting letters inside.
'the spanish' becomes 'el' ('the' in Spanish).
'ducat'+'iona'='ducationa'
'ducationa' put inside 'el' is 'EDUCATIONAL'.
(Other definitions for educational that I've seen before include "as an aid to learning" , "Relating to teaching" , "Providing knowledge" , "Academic" , "A docile aunt (anag) - instructive" .)