Star-crossed lover clothes me in jumper (5)
I believe the answer is:
romeo
'star-crossed lover' is the definition.
(I've seen this in another clue)
'me in jumper' is the wordplay.
'in' is an insertion indicator.
'jumper' becomes 'roo' (short for kangaroo).
'me' going within 'roo' is 'ROMEO'.
'clothes' acts as a link.
This may not be right. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for romeo that I've seen before include "Juliet's swain" , "He's on the lookout for it?" , "He loved" , "Peripheral figure" , "Ardent male lover" .)