Tokyo wrestler loses nothing in total (3)
I believe the answer is:
sum
'total' is the definition.
(I know that total can be written as sum)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for sum that I've seen before include "All one has" , "Arithmetic calculation" , "See 25" , "pupils find it a problem" , "Whole" .)