Unknown roused a disco, removing small sparkly belt (6)
I believe the answer is:
zodiac
'sparkly belt' is the definition.
'zodiac' can be an answer for 'belt' (I have seen 'Astrological belt ' mean 'zodiac' so perhaps 'belt' could also mean 'zodiac'). I'm not sure about the 'sparkly' bit.
'unknown roused a disco removing small' is the wordplay.
'unknown' becomes 'z' (algebra).
'roused' indicates an anagram (I've seen this in other clues).
'removing' suggests deleting specific letters.
'small' becomes 's' (abbreviation - e.g. clothes size).
'a'+'disco'='adisco'
'adisco' with 's' taken away is 'adico'.
'adico' anagrammed gives 'odiac'.
'z'+'odiac'='ZODIAC'
Can you help me to learn more?
(Other definitions for zodiac that I've seen before include "Belt divided into signs" , "Heavenly region" , "Band of sky much used by astrologists" , "Heavenly area" , "Set of star signs" .)