An eccentric minority are busily cleaning fruit (7,6)
'an eccentric minority' is the definition.
(I've seen this before)
'busily cleaning fruit' is the wordplay.
'cleaning fruit' can be anagrammed to 'LUNATIC FRINGE'.
Though, I am unsure how the anagram is indicated.
'are' acts as a link.
Can you help me to learn more?
(Other definitions for lunatic fringe that I've seen before include "Group of political party extremists", "fruitcakes around the edge?", "Most extreme members of an organisation", "Political fanatics", "Extreme political element".)