Like salt, for instance, covering one battered roll (8)
I believe the answer is:
sailorly
'like salt' is the definition.
(salt can mean a sailor)
'for instance covering one battered roll' is the wordplay.
'for instance' becomes 'say' (both can be used to introduce an example).
'covering' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'battered' indicates an anagram.
'roll' is an anagram of 'lorl'.
'i'+'lorl'='ilorl'
'say' enclosing 'ilorl' is 'SAILORLY'.
(Other definitions for sailorly that I've seen before include "tarry, maybe" , "salty?" , "Like one going by boat" , "Just like Jack" .)