"really enormous" is correct and usable in written English.
You can use it to describe something that is very large or impressive in size. For example, "The waves were really enormous today."
The numbers are going to look really enormous, but I don't think the stock prices will act dramatically.
The model gradually became more intricate: his method centres on crunching the data from as many previous examples as possible; imagine a really enormous spreadsheet.
I would like to put it down as a really enormous white elephant that doesn't have much in common with the regular economy of a regular state".
He explains plants and insect life with the detachment of a sight-seeing barker, and as head Yosian has brought a strange delight to a really enormous brotherhood.
"The Chinese Revolution and the establishment of the People's Republic of China brought about really enormous changes in the lives of women," said Gail Hershatter, a history professor and expert on Chinese women at the University of California, Santa Cruz.
"You know, I don't really have enormous confidence," she says, comforting Mia.
Which is really an enormous help, if you want to write".
It's really an enormous timesaver for people looking to find out what the news means".
Stephen King's reinforced the point that Saint Bernards really are enormous animals, and we're lucky that they're on our side.
"My Struggle" may be, like "All That Man Is," in flight from The Novel, but it is really an enormous bildungsroman.
