panz is on the right way - as usual:
- an "
old salt" is an older sailor with a lifetime of experience aboard ship, well-versed in the skills of seamanship and often also described as "crusty" (which is usually just a euphemism for "cranky").
"Salt" has been used as a synonym for "experienced sailor" since the mid-1800s by allusion to salt water and the salt spray which covers everything aboard ship.
- "
Salty dog" means essentially the same thing as "
old salt," a veteran and often aging sailor.
"Salty dog" is probably based on another term, "sea dog," again meaning a sailor with years of experience. The term "sea-dog," btw, originally was applied to the seals sailors often encountered.
Of course, don't confuse that with "The Original Salty Dogs", a dixieland revival band, founded in 1947 at Purdue University in West Lafayette, IN. (Named after the Salty Dog Rag/Blues) :wink: