The most common and most likely answer to this crossword clue is the 8 letter word YO-HO-HO
I've seen this crossword clue in Independent
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H
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More clues leading to the result YO-HO-HO
Buddy explains!
The straight part
We know that "refrain from old salt (sailor)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case refrain from old salt (sailor) = yo-ho-ho.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
Crossword Answer definitions
YO-HO-HO interjection- A cry associated with pirates and seafaring, originally a repetitive chant intended to synchronize workers performing some collective physical labour, such as hauling on a rope.