Mine is a recent discovery: Umbrella combines the Latin umbra, “shadow,” with the French diminutive “-ella.”
Umbrella = “Little shadow,” to shield one from the sun.
Hippopotamus = river horse - from the Greek hippos = horse, potamius = riverine
German for hippopotamus is nilpferd = Nile horse (nil pferd)
malaria - bad air
decimate - This was unexpected when I first learned it because of the change in the connotation over time. It’s usual meaning now is to to drastically reduce or obliterate something. Originally, it meant to kill one out of 10 (10 percent).
This follows for the Spanish sombrilla, sombra meaning shadow.
Or you may chose a paraguas para=for, agua=water (rain.)
When we are using a parasol we are using an implement para=for, sol=sun.
But it seems we use them interchangeably.
The word porcelain means, ultimately “of a young sow,” from a kind of weird association: porcelain is similar in texture to Cowry shells, which kind of resemble sow’s vulvae. Bam. Thread over.
In the words of Johnny Carson, I did not know that.
Barbarian: originally a Greek word for foreigners who didn’t speak Greek. Supposedly when they talked it sounded like they were just saying “bar bar bar”.
I’ve had people show skepticism about this one, but to me it’s completely believable. I’ve had several (ex-) friends do that irritating “ching chong chong ching” imitation of…some Asian language in the middle of anti-Asian rants.
That the words pen and pencil are unrelated. Pen from penne (feather), and pencil from penis.
Mine was unexpected, but only for me I’m guessing. It was one of those lightbulb moments just a few years ago when I realised that cigarette was actually derived from the original word cigar…as in little cigar or something? :smack:
The fings ya learn every day eh? 
“Bad” originally meant “homosexual.” It came to mean what it does now by the same process that the sentence “That’s so gay” among young people came to mean “That’s really bad”:
Ain’t no way I can top that, but until I read it, my answer was that insane literally means “unclean.” It has the same root as sanitary.
“Cosmetic” comes from the Greek word “kosmos” meaning “order”, the same root as the word “cosmos”.
Not exactly favorite, but I was surprised to learn the other day that all the various uses of the word “check” in the English language come from the game of Chess (and thus ultimately, from the persian word for “king”). I would’ve thought it would’ve been the other way around.
Vanilla is “little vagina” (in the sense of “little sheath”, thouhg, not “little female body part”).
I am going to keep all of my vanilla in porcelain from now on.
The name for the bird “Canary” derives from the Canary Islands - which were named for the wild dogs that used to roam on these islands (or possibly for some other reason that still amounts to naming the islands for some kind of dog Canary Islands - Wikipedia)
“Chicago” means “stinky onions.”
And apparently “fiddle” and “violin” come from the same root word.
“Flute” and “flatulence” come from the same word meaning “to blow.”
“Australia” and “Austria”, which are so often confused, have names derived from compass directions, but different directions. “Australia” comes from the Latin “Terra Australis”, meaning “Southern land”; “Austria” comes from the German “Österreich”, meaning “Eastern kingdom”.
The verb escalate is a back formation from “escalator”, which started as a brand name for a moving staircase.