Organised tour round Dutch house (5)
I believe the answer is:
tudor
'house' is the definition.
(royal house)
'organised tour round dutch' is the wordplay.
'organised' indicates anagramming the letters.
'round' indicates putting letters inside.
'dutch' becomes 'd' (common abbreviation).
'tour' is an anagram of 'tuor'.
'tuor' placed around 'd' is 'TUDOR'.
(Other definitions for tudor that I've seen before include "Elizabeth I, perhaps" , "Style of architecture in 15th century England" , "Name of a royal house" , "Welsh royal house" , "Regal family" .)