Second husband gets pixie storage space (5)
I believe the answer is:
shelf
'storage space' is the definition.
(I've seen this in another clue)
'second husband gets pixie' is the wordplay.
'second' becomes 's' (common abbreviation).
'husband' becomes 'h' (abbreviation).
'gets' means one lot of letters go next to another.
'pixie' becomes 'elf' (synonyms).
's'+'h'+'elf'='SHELF'
(Other definitions for shelf that I've seen before include "Ledge for holding things" , "support for books?" , "board" , "books supporter" , "Storage ledge" .)