Reduced the commission (3)
I believe the answer is:
cut
I believe this clue is a double definition.
'reduced' is the first definition.
(similar in meaning)
'commission' is the second definition.
(thesaurus)
'the' is the link.
(Other definitions for cut that I've seen before include "Slice, chop" , "Saw" , "Slash" , "drunk" , "Abbreviate" .)