In the book (which is an incredible read, BTW - Bram Stoker disappointed me in the literary-monsters department, but Shelley exceeded expectations) he’s referred to as The Creature.
Well played.
It was “Robot.” Duh.
That Morbius was very imaginative with names.
Middle initial, “T”.
Yep! In the novel the monster refers to Dr Frankenstein as his father and they do have a sort of twisted father-son relationship, so even if his first name is Adam then his full name would be Adam Frankenstein.
It’s one of those occasions where you can get a win over a pedant by being even more pedantic than they are. 
In the book, the monster has a few conversations with Victor, and has the following to say to him:
Always seemed to me that the monster thought of himself one of the Frankenstein family.
Frankenstein Jr!
As noted above, the name “Frankenstein” was used to refer to the monster early in the 19th century. It is referred to by that name in plays, and in countless political cartoons from the later 19th century. Peggy Webling* , who wrote the play that Universal bought, used it as the name of her monster. It certainly goes way back. You can blame the Universal film if you want, but it was already a well-established name for the creature, even then.
Shelley never did give the creature a name. It is referred to as “the wretch” (by Victor Frankenstein) and by other nouns. She certainly didn’t call it Adam, or Prometheus, or any such name. In fact, you could argue tat its lack of a name is another symptom of Victor Frankenstein’s not taking care and control of his own creation.
*She wrote it for Hamilton Deane’s company, which had just had a major success with Deane’s adaptation of Dracula. You could argue that Deane’s adapting both stories as plays is responsible for their importance to Universal, and thus to modern Pop Culture. After Horace Liveright brought Dracula to the States, Universal saw the appeal and bought the plasys, and bought Webling’s Frankenstein as well. John Balderstone (and Garrett Fort) rewrote them for the films, and the result is history. It’s interesting that the images from the films – the heavily Slavic accednted Bela Lugosi and the Frankenstein monster with his flat-topped head and bolt neck – are completely unlike what Deane first circulated in the English Theater circuit, and he wouldn’t have recognized the images, had they been transported back in time to his early theater days. By the time he died, the movie images were familiar all over the world.
Well, that’s a relief.
It’s only steen if the last syllable is spelled Stien. Since it’s spelled Stein, it’s pronounced stein.
What about the Frank part of the name? In German, would that be Frank as in “let’s be frank”, or Frahnk?
The same reason we pronounce his assistant’s name “Ee-gore” instead of “Eye-gore.”
Because only the Litvaks, the English, and other degenerates pronounce -stein as -sti:n? 
ETA:
More seriously, it seems like German -ei- has gone through different vowel shifts in different dialects, becoming something like \aj\ in Hochdeutsch while it was \ei\ among Middle-European Juden, then \i:\ among Jewish Americans, which is what Mel Brooks was having fun with.
You guys know you’ve been whooshed by Tripolar there, right?
I was playing along.
Growing up in the 1960s, ‘Frankenstein’ was the monster, and nobody gave a damn about his creator. I think Young Frankenstein remedied that to some extent.
To inspire the creation of restaurants, ballpark promotions, etc. centered around the combination of hot dogs and beer.
Finally!
Also, wasn’t he the one with the hump?
Actually, Viktor Frankenstein’s assistant’s name is pronounced either “Fritz” (Frankenstein) or “Karl” (Bride of Frankenstein). 
Do you pronounce “Fritz” with a long or short i? Does “Karl” rhyme with “snarl” or “coral”?
“Frights.”
“Fritz” was the name of Frankenstein’s assistant in the very first stage adaptation of the story, way back in 1820. I don’t think Peggy Webling or the Universal screewriters were aware of it, though. “Fritz” is a common German name, and was often used by the English as a German name when they needed one in a drama.
At first I thought that that play Fritz was added for the most common literary reason – to give Victor Frankenstein someone to talk to, giving an excuse for revelatory dialogue. But apparently they originally intended stage Fritz to be a silent part.
Whatever the reason, Fritz was eventually given a LOT of dialogue, and did serve as the font of exposition. You can’t keep a good trope down.
It’s of interest that Fritz, either on stage or in the 1931 film was a hunchback. Neither was Karl in Bride, or even Bela Lugosi’s Ygor in Son and Ghost. It wasn’t until House of Frankenstein in 1944 that we had Daniel ---- Daniel, fer cryin’ out loud! Can you imagine a more harmless name? – as the first Hunchbacked Assistant. He was played by J. Carroll Naish, an actor who deserved better. At least he got to be the Hunchbacked Assistant to Boris Karloff.