Institution founded by sailor and Turk (5)
I believe the answer is:
abbey
'institution founded' is the definition.
I can't tell whether this definition defines the answer.
'sailor and turk' is the wordplay.
'sailor' becomes 'ab' (abbreviation for able seaman).
'and' is a charade indicator (letters next to each other).
'turk' becomes 'bey' (I can't explain this - if you can you should believe this answer much more).
'ab'+'bey'='ABBEY'
'by' is the link.
Can you help me to learn more?
(Other definitions for abbey that I've seen before include "Monks' abode" , "Monastic church" , "Church (once linked to convent or priory)" , "Religious building" , "Home for monks or nuns" .)