The sacrifice of the mass? (8)
I believe the answer is:
hecatomb
'the sacrifice' is the definition.
(hecatomb is a kind of sacrifice)
'of the mass?' is the wordplay.
I cannot really understand how this works, but
'of' could be 'o' and 'o' is located in the answer.
'mass?' could be 'm' (symbol used in Physics e.g. f=ma) and 'm' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for hecatomb that I've seen before include "sacrifice victims" , "major sacrifice" , "Large-scale sacrifice" , "great public sacrifice" , "mass slaughter" .)