Preserve water slide around New Year (7)
I believe the answer is:
chutney
'preserve' is the definition.
(Indian fruit preserve)
'water slide around new year' is the wordplay.
'water slide' becomes 'chute' (chute can mean a water slide).
'around' is an insertion indicator.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'year' becomes 'y'.
'chute' placed around 'n' is 'chutne'.
'chutne'+'y'='CHUTNEY'
(Other definitions for chutney that I've seen before include "Spicy Indian condiment" , "Cold sauce eaten with curry" , "Condiment made from fruit or vegetables" , "Spicy preserve" , "Spice in it" .)