Time's cut short with this, might we presume? (6)
I believe the answer is:
scythe
'time's cut' is the definition.
'scythe' can be an answer for 'cut' (I've seen this before). I am unsure of the 'time's' bit.
I don't understand how the rest of the clue works.
(Other definitions for scythe that I've seen before include "Implement with curved blade" , "Bladed cropping implement" , "Tool for cutting grass with blade on long pole" , "Manual tool of reaper" , "Harvesting tool" .)