King had this made specially for crossing river (5)
I believe the answer is:
dream
'king had this' is the definition.
(Martin Luther King - 'I Have a Dream')
'made specially for crossing river' is the wordplay.
'specially' indicates anagramming the letters (I've seen this in other clues).
'for crossing' is an insertion indicator (some letters go around or cross others).
'river' becomes 'r' (abbreviation for river).
'made' with letters rearranged gives 'deam'.
'deam' placed around 'r' is 'DREAM'.
(Other definitions for dream that I've seen before include "Trance" , "Night-time fantasy" , "It's experienced during sleep" , "Switch off" , "Sleeping experience" .)