They may be placed but are best misplaced (4)
I believe the answer is:
bets
'they may be placed' is the definition.
(I've seen this in another clue)
'are best misplaced' is the wordplay.
'misplaced' is an anagram indicator (letters in the wrong places).
'best' is an anagram of 'BETS'.
'but' acts as a link.
(Other definitions for bets that I've seen before include "Wager, stake" , "plays" , "Makes wager" , "Gambles" , "Wagers" .)