One cuts two thirds of time off (6)
I believe the answer is:
sickle
'one' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for sickle that I've seen before include "One stands for Communist" , "Short-handled reaping tool" , "Reaping hook" , "Reaping implement" , "field-worker being a trimmer" .)