Promise the return of some imprisoned rowdies (4)
I believe the answer is:
word
'promise' is the definition.
(as in 'I give you my word')
'return of some imprisoned rowdies' is the wordplay.
'return of' says the letters should be written backwards.
'some' says the answer is hidden in the clue (some parts of the word are used).
'drow' can be found hidden inside 'imprisoned rowdies'.
'drow' backwards is 'WORD'.
'the' is the link.
(Other definitions for word that I've seen before include "Puzzle with solutions reading the same down as across" , "Promise; news" , "usually comes with more than one letter" , "Element of language" , "Term" .)