More formal phrase for "throw someone off"

Question

Is there a more formal phrase with the same meaning of "throw someone off"?

I want to use the phrase exactly how I am sure everyone is used to it being used. I want to say that something unexpected caused someone to lose their focus or momentum.

For convenience, here is a description from TheFreeDictionary of the phrase "throw someone off":

Throw someone off - to interrupt and confuse someone; to mislead someone.
Example usage - The interruption threw me off, and I lost my place in the speech.
Example usage - Little noises throw me off. Please try to be quiet. Your comment threw me off.

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Background

I was ironically writing an answer for another question on this site, when I wanted to use the phrase but in a more formal setting than I have normally heard it used.

The question was discussing talking with servers at restaurants, specifically while ordering drinks, so I'll use that example.

Let's say you are at a Denny's restaurant and the server asks, "What can I get you to drink?". You respond with, "A fizzy soup", which is of course the nickname for Coke where you're from. You've forgotten that you're out of town and the server has no clue what a "fizzy soup" is. She is thrown off by your response. After explaining yourself you might say, "Sorry that I threw you off!".

Now let's say you are at one of the best 5 star restaurants around, and you make the same mistake.. Your server is thrown off. You'd like to apologize, so what can you say? I feel like saying, "Sorry that I threw you off!" would actually also throw off the server because of how informal it sounds.

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My attempts at substitutions

In a formal setting, I would probably substitute "Sorry, I didn't mean to throw you off." for "Sorry, I didn't mean to confuse you.". I might substitute "Were you thrown off?" for "Were you distracted?".

But I don't think either one of my substitutions carry the same meaning as "thrown off".

Confused and distracted adequately describe the state of someone who was "thrown off", but lack the description of the cause of the state that I would like my replacement phrase to have. "Thrown off" implies the cause of confusion or distraction was something unexpected such as an interruption.

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Questions

Is there a more formal phrase with the same meaning of "throw someone off"?

Is there any phrase or wording that carries the same meaning as "throw someone off", even ignoring formality?

Answer 1

Consider,

put one off [one's] stride

Also, put one off one's stroke (chiefly BrEng)

Interfere with one's progress, distract or disturb one, as in The interruption put her off her stride for a moment, and she took several seconds to resume her train of thought, or The noise of the airplanes overhead put her off her stroke, and she missed the next ball. The first term, first recorded in 1946, alludes to the regular pace of a walker or runner; the variant, first recorded in 1914, alludes to the regular strokes of a rower.

The American Heritage® Dictionary of Idioms

throw one off the track

Fig. to cause one to lose one's place in the sequence of things. The interruption threw me off the track for a moment, but I soon got started again with my presentation. Don't let little things throw you off the track. Concentrate on what you're doing.

McGraw-Hill Dictionary of American Idioms and Phrasal Verbs

make one lose one's train of thought

lose one's train of thought

Fig. to forget what one was talking or thinking about. Excuse me, I lost my train of thought. What was I talking about? Your question made the speaker lose her train of thought.

McGraw-Hill Dictionary of American Idioms and Phrasal Verbs

train of thought

A succession of connected ideas, a path of reasoning, as in You've interrupted my train of thought; now what was I saying? This idiom, which uses train in the sense of "an orderly sequence," was first recorded in 1651, in philosopher Thomas Hobbes's Leviathan.

The American Heritage® Dictionary of Idioms

Answer 2

disconcert, faze

more formal verbs, perhaps

She was fazed by the big smear of ketchup on his shirt.

They were disconcerted by the Queen's lackadaisical demeanor regarding the Palace's protocol.

Answer 3

Discombobulate

To throw into a state of confusion.

Quote from Sherlock Holmes(film):

Sherlock Holmes: [voice-over] This mustn't register on an emotional level...

[in slow motion]

Sherlock Holmes: First, distract target...

[Holmes flicks a handerchief in front of his opponent's face]

Sherlock Holmes: Then block his blind jab, counter with cross to left cheek. Discombobulate.

[Holmes claps his hands over his opponent's ears]

Answer 4

Confuse

Given the examples in your question, the most appropriate word would be confuse. The issue is that if you order a 'fizzy soup' and the server is unfamiliar with the phrase, they probably wouldn't consider themselves 'thrown off' so much as just unclear, or "confused" as to what it is that you actually desire.

If you ask if they were 'distracted' or 'confused', it may come across as if you are leveling the responsibility of their confusion on them. The most important thing would be to apologize for 'confusing' them, whereby you accept the responsibility for their confusion (if indeed you were responsible.)

Sorry I threw you off

to me sounds unnatural, whereas

I apologize for causing any confusion, I'd like a Coke please.

sounds much more natural and formal, if that's your thing

From Merriam-Webster:

confuse verb
. . .
2b : to disturb in mind or purpose : THROW OFF
The directions she gave confused us.

Answer 5

Adding for the variety, you could say:

"Sorry I guess I caught you off guard with "fizzy soup" for a beverage. I didn't mean to trip you up on that one. I meant a Coke, I believe. You do call it a Coke here, right?"