Is there an English expression to convey the idea that the interlocutor is being a bit too full of themself and needs to be a little humbler?
In Italian we have an expression abbassare la cresta that literally translated is “lower your comb/crest”; are there any corresponding expressions for this in English?
"Get off/come down off your high horse":
Fig. to become humble; to be less haughty. It's about time that you got down off your high horse. Would you get off your high horse and talk to me?
(The Free Dictionary)
expletive you and the horse you road in on", it's implied that the horse is a high horse.
"Get over yourself"
This is widely used in America (at least the parts I'm familiar with). It implies that the person being spoken to is overly impressed or pleased with himself, and needs to "get over" that feeling, or return to a more impartial attitude.
Your Italian phrase references a strutting rooster. There are several parallel phrases in English, my favorite of which is from the movie Star Wars:
Great, kid. Don't get cocky.
It is spoken by Han Solo after Luke Skywalker (i.e., the kid) has just destroyed his first TIE fighter. IMDB.
Any imperative to not be cocky is urging the hearer to not be like a rooster, in other words, to be humble. (Of course, the word in English for a male chicken is a cock, but this has taken on an unfortunate connotation. However, the adjective form of cocky does not share the same connotation.)
You may say: you are getting too big for your boots.
Definition and example from Cambridge dictionnary: behaving as if you are more important than you really are. He's been getting a bit too big for his boots since he got that promotion.
Not polite, however: That man is full of himself. He needs someone to pull out the cork.
I think that latter comes from Italian, but I'm no good with that language.
"Get over his/herself" might be the best answer given so far. Its specifically used most often towards a subject that regards themselves as entitled to a particular esteem or honor and feeling unquestionable is certainly an example of such a case.
References to "high horses" could work, but tend to invoke connotations of morality more so than pride.
Myself, I might say he/she needs to be:
However, this is suggests a more passive role for the subject, suggesting that it needs to be acted upon, rather than the subject itself carrying the responsibility to act.
Expression such as "get real" or "get a clue" might be commonly be used in the latter sense. Though they are less specific to pride, they are often used in pride-related cases.
There are plenty of ways to describe such a person. You might say they are self-absorbed, self-centered, or think too highly of themselves. However, not many expressions dictate what they should do about it. Likely because not many people have had much success telling them anyway.
Which reminds me of an applicable phrase that my Swedish grandmother would say about my Danish grandfather:
"You can always tell a Dane, but you can't tell him much!"
If the person is talking like a politician giving a speech, you could tell them to "get off your soapbox."
If the person is belligerent and trying to start a fight, you could say they "have a chip on their shoulder."
If you want to be poetic, you could say "Pride comes before a fall" (originally from the Bible and repeated by Shakespeare in Macbeth).
Some options include:
If by interlocutor you mean emcee (master of ceremonies), then "ungracious" may be the word you are seeking. For the other meaning of interlocutor, we have an expression in the US, "too big for his britches."
