Old sailor's cure? (4)

I believe the answer is:

salt

I believe this is a double definition.

'old sailor's' is the first definition.
(old-fashioned nickname for a sailor)

'cure?' is the second definition.
(thesaurus)

(Other definitions for salt that I've seen before include "Condiment - old sailor" , "A defence against ice" , "Liveliness" , "Sea dog" , "Wit; sodium chloride" .)

I've seen this clue in The Telegraph.

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