Trade cut affected supplier of eye drops (4,4)
I believe the answer is:
tear duct
'supplier of eye drops' is the definition.
(tears drop from tear ducts in the eye)
'trade cut affected' is the wordplay.
'affected' indicates an anagram.
'trade'+'cut'='tradecut'
'tradecut' is an anagram of 'TEAR-DUCT'.
(Other definitions for tear duct that I've seen before include "source of visible upset" , "Passage for the liquid secreted from the eye" , "Passage for fluid from the eyes" , "A crying need" .)