Fantastic. Someone asks a simple question about two simple words in a song and we've been taken on a (ahem) 'roller'-coaster ride through maritime and sailing lore, a couple of thousand years of history, dipped in and out of several languages and cultures, been round the world half a dozen times, taken a break for a joke or two...And they said folk music and the internet would never mix.
By the way - what's the answer??!!