Stupefaction is the noun form for the state of being stupefied, which in turn means to be dumbfounded or surprised, or to cause someone to lose their wits or their ability to reason or process information.
This noun does not a have a plural form. Stupefactions is incorrect. The peak in popularity for stupefaction occurred around the turn of the twentieth century and has been on a decline since then.
The adjective form of stupefy is stupefying.
Most commonly this word is misspelled and mispronounced as stupefication, where users insert an extra syllable.
Cronenberg’s movie seems bound to stupefy Hollywood as much as Sunset Boulevard did six decades ago, unless it becomes the industry’s Rocky Horror Picture Show, with private screenings in private screening rooms from Bel-Air to Malibu, viewers reciting in unison all their favorite lines. [LA Magazine]
Not only will he stupefy the audience with his visual close-up Magic but also with his skills in ‘Mentalism’ where he reads people’s minds.
After the famed line, Mattei’s Count stood there in shock, a tremendous dramatic pause. His reaction was one of stupefaction mixed with pain. He was angry, but his realization he had been duped seemed to come as a painful assault on him. [Latin Post]
On varnishing day at the Royal Academy, Turner dabbed highlights on his paintings and, to the stupefaction of his colleagues, seemed to animate them by doing so, startling them into life at the very moment when he should have left them fixed and finished. [The Guardian]
Stupefaction can, however, lead one to stew so much that one does something a touch stupid. [CNET]
Details about the White House scamper of knife-wielding Omar Gonzalez are stupefying. [The Star Press]