Beginners in South Pacific often employ partner (6)
I believe the answer is:
spouse
'partner' is the definition.
(I know that partner can be written as spouse)
'beginners in south pacific often employ' is the wordplay.
'beginners in' indicates taking the first letters.
'employ' becomes 'use' (synonyms).
The first letters of 'south pacific often' is 'spo'.
'spo'+'use'='SPOUSE'
(Other definitions for spouse that I've seen before include "mate" , "Possibly wife" , "Elizabethan dance" , "Very hot and dry" , "Married partner" .)