Rapid measuring system Zeno introduced, oddly abandoned (8)
I believe the answer is:
meteoric
'rapid' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
(Other definitions for meteoric that I've seen before include "Like a small body in space" , "Erotic me being suddenly brilliant" , "Fast; brilliant" , "Brilliant, as a shooting star" , "(Of change) very rapid" .)