Evan Morris, author of "The Word Detective" column that used to run in papers and alt weeklies, used to perennially comment that acronyms in English were quite rare until roughly WW1-WW2, and as such etymologies involving them ("to insure promptness", "port out starboard home", etc.) are virtually always false.

More to the point, TFA lays out various evidence why this particular theory is unlikely.

> "to insure promptness"

As in tipping service? It'd be ensure anyway, surely?

> As in tipping service?

The same. For whatever reason false etymologies based on acronyms abound, with "tip" and "posh" being among the better-known. There's also "for unlawful carnal knowledge" for fuck, "gentlemen only ladies forbidden" for golf, "constable on patrol" for cop, etc. I've even heard people claim rap derives from "rhythm and poetry". But basically they're all bunk, apart from words of quite recent coinage.

(I might add that tons of false etymologies without acronyms float around as well - "mind your Ps and Qs" being related to pints and quarts, stuff like that. Morris used to blame tour guides as being the worst culprits of keeping such things alive.)

Tip is old enough (1755) that they where the same word.

The cynic would be mostly right, at least for much of the history of English, as for hundreds of years insure and ensure were simply spelling variants, and had no more difference between them than theatre and theater.

However, in the middle of the 19th century some began to find fault with this, and proposed assigning meanings to ensure, insure, and assure in more orderly fashion.

https://www.merriam-webster.com/words-at-play/how-to-use-ins...

PS: Tip is unlikely to have started as an acronym in either case.

"Port Out, Starboard Home" by Michael Quinion is a nice book about 'folk etymologies' that covers these and many more. He gives the real origin where it's known.

Another example is "fuck" which probably doesn't stand for "for unlawful carnal knowledge.[0]"

[0]https://www.snopes.com/fact-check/what-the-fuck/

As the article mention, everyone have their favorite theory. This one sounds particularly unbelievable though. "Jesus Amen Save our Souls" is not even a meaningful sentence. So it is likely a backronym from JASS rather than the other way around.

"reality may avoid the obligation to be interesting, but hypotheses may not".

It's a good story, let it live.

It's not a good story. Most slaves weren't even allowed to read or write, and flipping 's' to 'z' is a ridiculous "code."

I would immediately jump to unbelieving due to anecdotal nature of this claim but these are kinds of stories that tend to be propagated through stories told