Torches moving abeam in uncertain motion (9)
I believe the answer is:
'torches' is the definition.
(I've seen this in another clue)
'moving abeam in uncertain motion' is the wordplay.
'moving' indicates anagramming the letters (letters are moved around).
'in' is an insertion indicator.
'uncertain motion' becomes 'flux' (flux is continuous movement).
'abeam' anagrammed gives 'ambea'.
'ambea' put into 'flux' is 'FLAMBEAUX'.