Yob
I am reminded of the word "redrum" on the door in one of
Stephen King's novels: was it "The Shining"?

Look to none other than John Tukey, inventor of the fast Fourier transform, for coinages with backwards syllables: spectrum --> cepstrum, frequency --> quefrency, analysis --> alanysis, ...
All of these come from his landmark paper on the analysis / alanysis of seismic data using frequency analysis of frequency data (two levels of frequency analysis).
Tukey's coinage of the "bit", his invention of the FFT, his work on exploratory data analysis, and his Bell Labs career are legendary, but his coinages are certainly obscure. Practitioners and researchers working in the area of automatic speech recognition have adopted the "cepstrum" for audio signal analysis.

was it "The Shining"?

It was. Yob, if I am not mistaken, is from Polari, a kind of cant.

Part of the NOTES:
There are not a lot of words in the English language that are coined from the backward spelling of another word.

What if this were done to the other day's Word? We'd have ygyzys!

Which would be reanalyzed as a plural, giving us ygyzy in the singular.

Thanks.

My brother and I got tired of everyone saying "yo, 'sup?" so we started saying "pus, oY?" It's amazing how you can use pig latin or even just say the word backwards in normal conversations when you wan to confuse people.

50% of the people I speak with are so confused
as it is, they'd thing "pus,oy" was just a spoken form
of texting.

ygyzy: a condition afflicting those who believe they are funny. *
This is NOT a slam to Faldage; just a play on the way the word could sound. Ask me, if it's too far a stretch...

'Fraid not, zm - it comes from Cockney "backslang", a cant to confuse police, informers and others from whom the denizens of East London wished to hide their intentions (mostly nefarious!) and thoughts (mostly unprintable!)[google "backslang" - there is a wealth of sites explaining it]
So,
YOB = boy
ELRIG= girl
YENOM = Money
TAF SAY = Fat ***!
NAMOW = Woman
DELO =Old
YEEBAB = Baby

This is in addition to Cockney Rhyming slang, like "apples and pears" = Stairs; "whistle and flute" = suit; "bread and honey" = money. This was made less comprehensible by only the first word of the pharase being used, making it virtually incomprehensible to the uninitiated!
E.G.
" I went darn the frog in me new titfer and best whistle with plenty o' bread in me sky, on me way to the four, when me delo namow comes arter me!"

= " I went down the road (frog & toad) in my new hat (tit for tat) and best suit (above) with plenty of money (above) in my pocket (sky rocket)on my way to the races (four aces) when my old woman (i.e., wife) comes after me."

it comes from Cockney "backslang"

Ah, well, should've looked into before going by memory.

There is a French cant, Verlan, where syllables are reversed. For example, cité 'city' > té-ci > téss. Some single syllable words just ended up backwards. Polari tends to have a lot of loanwords from other languages, such as Yiddish, Romanian, etc.

AS you say, polari is almost entirely made up of loan words - including backslang. e.g. lyrig - girly, as in, " that lyrig has real bona lallies. Shame she's a chavering donna!"

There's lots of Italian loans [polari derives from It "parlare = to speak] and quite a few Romany i.e. gypsy, words (rather than Romanian, strictly speaking, although I guess there is some connection there.) A very flamboyant and colourful language.