Cook pauses to wrap duck left in promotion (8)
I believe the answer is:
espousal
'promotion' is the definition.
(thesaurus)
'cook pauses to wrap duck left' is the wordplay.
'cook' is an anagram indicator.
'to wrap' means one lot of letters goes inside another.
'duck' becomes 'o' (resembles zero - 'duck' in cricket).
'left' becomes 'l' (common abbreviation).
'pauses' is an anagram of 'espusa'.
'espusa' placed around 'o' is 'espousa'.
'espousa'+'l'='ESPOUSAL'
'in' is the link.
(Other definitions for espousal that I've seen before include "Acceptance with approval" , "Adoption (of a cause) - USA's pole (anag)" , "Backing, support" , "old-fashioned marriage" , "Favourable reception" .)