One of those mixed-up scraps (5)
I believe the answer is:
melee
'mixed-up scraps' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'one of those' is the wordplay.
I cannot really understand how this works, but
'one' could be 'me' (a setter might use 'one' to humourously mean 'me') and 'me' is found in the answer.
The remaining letters 'lee' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for melee that I've seen before include "Confused crowd" , "Fracas" , "A confused fight or muddle" , "Affray; muddled group" , "Scrimmage" .)