They might be fancy, sleek — can be worn by many? (9)
I believe the answer is:
necklaces
'they' is the definition.
Both the definition and answer are plural nouns.
Perhaps you can see a link between them that I don't see?
'fancy sleek can be worn by many?' is the wordplay.
'fancy' is an anagram indicator.
'be worn by' means one lot of letters goes inside another (outside letters are worn by those on the inside).
'many?' becomes 'c' (C is the Roman numeral for 100).
'sleek'+'can'='sleekcan'
'sleekcan' anagrammed gives 'neklaces'.
'neklaces' going around 'c' is 'NECKLACES'.
'might be' is the link.
Can you help me to learn more?
(Another definition for necklaces that I've seen is " Items of jewellery".)