Cut the supporting workers' basic pay, ultimately (6)
I believe the answer is:
scythe
'cut' is the definition.
(I've seen this before)
'the supporting workers' basic pay ultimately' is the wordplay.
'supporting' means one lot of letters go next to another (in a down clue, some letters go below others).
'ultimately' suggests the final letters.
The final letters of 'workers basic pay' are 'scy'.
'the' put after 'scy' is 'SCYTHE'.
(Other definitions for scythe that I've seen before include "Old hand-held cutter of hay" , "Cut down - grass-cutting implement" , "Old-fashioned hand-held hay mower" , "Large sickle" , "Agricultural tool" .)