Man dispatched to collect gravlax oddly absent (7)
I believe the answer is:
servant
'man' is the definition.
(man can mean someone's personal servant)
'dispatched to collect gravlax oddly absent' is the wordplay.
'dispatched' becomes 'sent' (I've seen this before).
'to collect' means one lot of letters goes inside another (inserted letters are collected by others).
'oddly absent' means one should take alternating letters (odd-numbered letters removed).
The alternating letters of 'gravlax' are 'rva'.
'sent' enclosing 'rva' is 'SERVANT'.
(Other definitions for servant that I've seen before include "Eg, a footman or maid" , "Perhaps help" , "'Flunky, lackey (7)'" , "eg Sancho Panza" , "Domestic help" .)