There are lots of words that we use in formal writing that were only beginning to be tossed around in the nineteenth century, like ‘noticeably,’ which first appeared in print in 1845, and ‘blithering,’ which was coined by Punch in 1889.
A colloquialism is a word, or phrase, that is used in informal speech, but not in formal writing. English had not yet been standardized by the nineteenth century, which makes identifying colloquialisms that were colloquial within the period trickier. There were no set rules about which words could and couldn’t appear in formal writing, but upper- and middle-class Victorians often had strong opinions about what words counted as slang.
“I do not, as you know, take sufficient interest in dress to be able to describe the new fashions. Dress is a bore. That is slang again, but never mind; Arthur says that every day.” – Lucy Westenra in Bram Stoker’s Dracula (1897).
Bram Stoker’s character of Lucy Westenra provides an interesting study of late-Victorian opinions on language. In the same letter that she writes the sentence: “Just fancy!” she calls the noun ‘bore’ slang. I could write a whole book on this problem alone, but the key is that there’s nothing random about the quirky opinions women, like the character of Lucy Westenra, had about language.
As the nineteenth century drew to a close, women’s intellectual abilities were on trial, as women began entering university programs and demanding a role in politics. Moreover, they lived in a world that was literally inventing itself as it went along. It seemed clever to turn the verb ‘notice’ into the adjective ‘noticeably.’ If you are writing historical fiction, your character might try it with other verbs as well.
Words that you invent this way will be appropriate to the period and can add some levity to scenes that require it. ‘Grieve’ can become ‘grieveably’ and ‘shout’ can become ‘shoutably.’ I can’t create the context that those words will be hilarious in, but I know you’ll think of something!