How common is the word "hubris" in spoken language?

hubris

would stick out very uncomfortably in informal speech, and is pompous sounding even in academic writing. Even if a word is highly used, or rarely, it will still have other features like vulgarity/tabooness (like very common swear words), technical context (carburetor), or, as in this case, register (like perhaps or indeed). That is to say that frequency isn't the only thing that gives a word color or appropriateness.

As a style recommendation, I would not recommend using the word hubris around your football hooligan comrades, they might make you pay for the next round. And unless your tea party pals are discussing Greek tragedy, it make a monocle or two drop. But it's totally on for the crossword gang.

As to its frequency though in writing, here are the words of mostly equivalent frequency:

impasse imp immerse ilk humerus hubris honeydew homophobia hindrance hiker highfalutin

These terms are all easily recognizable by adults. They are not rare, but they are also not everyday words (hiker seems out of place here, I'd expect that to be much more common). These words are more educated, like impasse, humerus, and hindrance.

For perspective with the corpus used, these are around the 20140 index of frequency, where the list starts:

• 1: you, I, the, to, a
• 1000: plenty, guilty, jerry, fired
• 10,000: unorthodox, trusty, trough, trolly
• 15,000: forger, fictitious, fizz, feasible
• 20,147: hubris, honeydew, homophobia, hindrance
• 30,000: dermis, dermatological, deregulation, deputation.

Those at the 30K mark are still very recognizable.

Note the Zipf pattern in action: the less frequent items will have less difference in frequency to the point that many will have the same number of occurrences and then by the extraction method I used, they are sorted alphabetically together.

This short list was created using word frequencies from https://www.researchgate.net/project/Word-prevalence-measures-for-62K-English-lemmas. The source doesn't have to be terribly accurate; a lot depends on the corpus but presumably with a large enough corpus a difference of one or two mentions may put you in a not too distant bin.

As noted, its usage has been growing constantly in the English language:

According to Collins Dictionary the term hubris is:

• Used Occasionally.

Hubris:

• In modern usage, hubris refers to extreme arrogance that can often cause a person to look ridiculous. It can be applied in situations of business, school, or any social interaction. People might act with hubris if they lead a meeting as though they are completely knowledgeable on information they've never learned. Similarly, a student who believes they are better than everyone else because of a superior test grade would have considerable hubris.

• The contemporary use of hubris can be applied in any situation relating to overbearing pride. The use of hubris is meant to emphasize just how intense one's arrogance can be. Hubris indicates supreme overconfidence, which in turn can lead to foolishness or even a downfall. An inflated ego is not built on a solid foundation of fact or knowledge; therefore, anyone with hubris tends to isolate or destroy their social standing or relationships. Hubris is never a good thing because it is excessive, damaging pride.

(wineverygame.com/words)