Quiet pixie on the ledge (5)
I believe the answer is:
shelf
'ledge' is the definition.
(synonyms)
'quiet pixie on' is the wordplay.
'quiet' becomes 'sh' (both can be said to tell someone to be quiet).
'pixie' becomes 'elf' (synonyms).
'on' is a charade indicator (letters next to each other).
'sh'+'elf'='SHELF'
'the' acts as a link.
(Other definitions for shelf that I've seen before include "Horizontal surface for holding things" , "Horizontal surface for holding objects" , "sort of life" , "Rock ledge; underwater bank" , "Wall fitting for books, etc" .)