Material gain, in the end, only frittered away (5)
I believe the answer is:
nylon
'material' is the definition.
(I know that nylon is a type of material)
'gain in the end only frittered away' is the wordplay.
I cannot really see how this works, but
an anagram of 'only' is 'nylo' which is within the answer.
A single letter 'n' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for nylon that I've seen before include "Man-made fabric" , "Synthetic material used in textiles" , "Artificial fibre" , "Polyamide" , "may be damaged by running" .)