Completely agree, the cultural context is very important. To the majority of Britons, these sorts of things are completely normal and somewhat expected (even if they're less common in some areas). In America, such things would almost certainly turn heads (as I'm sure some American slang would here, though much less so thanks to the significant exposure to American culture).

discrimination is in intent Actually the bulk of discrimination happens without explicit intent. Even people who think of themselves as objective can act discriminatory. I mean of course the guy didn't mean to be sexist. Imagine the level of douchebaggery if he did.

@CapeCode yeah, discrimination doesn't have to be intentional or even malicious, but it does generally have to have the intent of treating people differently. It's really tricky phrasing, I'm not sure how to convey the distinction I'm trying to make :/

I agree with @CapeCode: we have a variety of scientific studies to show that discrimination can be unintentional, and in fact these are the most insidious forms of discrimination. Moreover, in this case, the specific words are precisely what is in contention. Finally, I couldn't help but notice that your "run through the potential ways to greet you" doesn't include any of the ones that I (a professor at a US university) would find appropriate. Is this because you actually don't know the appropriate forms or for some other reason?

@CapeCode Hmm, I think this is where things fork off in to discussion of the difference between bias and discrimination and at what point the former becomes the latter. Bias is probably more of an issue than discrimination since bias usually implies not being aware of it at the time, though I won't defend either. Part of the difficulty would certainly be that of separating communication into intent, content and reception.

@PeteL.Clark To the honorifics specifically, I would assume that if the person holds a qualification the title would be used but iirc it's bad form to assume a title qualification. That covers titles like Dr and Rev. I know that at some levels Professor is a title as well as position but as you guess I don't know the appropriate qualifications for that becoming correct. The list wasn't meant to be exhaustive or entirely serious, honorific precedence is a bit of a headache for attempting to be the former.

I should also probably be clear that my point wasn't to give offence but rather to imply that the student in question may not have meant to give offence either. Personally I'd address someone in the manner they are introduced to me... If someone says "I'd like you to meet Professor Jones" that's how I'm going to refer to them until I'm corrected :)

@Kaithar: Because female faculty members are often not treated with the respect they deserve -- to an extent which contributes to the under-representation of women in many academic fields, including my own -- I and many other academics do not view this topic with much levity. If your answer is not sincere, please modify it. If you do not know an appropriate answer, please do not leave an inappropriate answer. It is not a positive contribution to this serious issue.

Shaking my head at this answer... I just can't believe it. "Discrimination is in intent" is just so so wrong. The wrongness of this belief has been demonstrated absolutely conclusively many many times and upholding this myth damages progress. I'm sorry I have to be strong in my words here. And: "Tactfully, very very tactfully." Why such a big emphasis on this (i.e. preserving his feelings)? She's the professor; she is entitled to just plainly explain that she does not wish to be addressed like that.

And I must strongly disagree with "modern culture makes it considerably harder to honestly flatter someone without it being interpreted as sexist". This is another common myth. After all, if he's said "Dear Professor Lastname, your class was excellent; I think you are an outstanding teacher" that would have been very easy non-sexist flattery. Also, what is normal in other parts of the country or other contexts is irrelevant; the context is student emailing professor and there are well-established, conventional salutations for this.

And again on the point of what is normal in the north of England/among the older generation. The point is that the cultural norms themselves can be sexist. It is perfectly plausible that what is normal in the north of England is sexist. Sexism is embedded into our culture and our institutions. So this person can be being both sincere and sexist. And I'm sorry but the suggestion that she should say "while I'm flattered" is just ugh.

@Thompson So you feel the best way to maintain professionalism is to not only assume the worst of people but also attack straight off the bat based based on those assumptions? Then again, you've apparently got nothing better to do than rip apart every sentence of my answer. I can only assume that you can't distinguish between "discriminate" and "bias". I can also only assume that you can't read where I said they're both wrong. So quit painting my words as being something they're not.

@PeteL.Clark With respect, telling faculty members of any gender to react in a hostile manner isn't going to help them. I don't know much about the politics at your particular institution but I do know that diplomacy and tolerance should be practised even when you are correct. Although, if you're suggesting that I should modify my response specifically because I'm responding to a female academic, you might want to consider what message that sends. But maybe I'm wrong in thinking that being rude to students is a good way to get them to learn.

@Kaithar: I certainly did not tell anyone to react in a hostile manner! I've explained what I found problematic about your answer and left an answer of my own. I'm sorry to have written something that was misunderstood so severely. On the other hand, it may be that the person who has misunderstood what I said about American academic culture is neither American nor an academic; if so, this lack of understanding seems mostly harmless. So I will let things rest for now. If you continue to participate on this site, maybe we can take it up again later.

@PeteL.Clark would you prefer "rude"? Since your answer feels the need to call everyone else here sexist, I would have thought hostile would be an appropriate description. Perhaps you missed the part where the question was originally specifically "How do I deal with this sexist email" rather than just inappropriate? Sorry if I've offended your sensitivities sense of equality by failing to take OPs gender in to account and by not making assumptions about her experiences based on her age and gender... I prefer not arguing from self defeating propositions.

@Kaithar: "Since your answer feels the need to call everyone else here sexist" No, I haven't done that. But unequal treatment of women in academia is a big deal to me: I am currently the coordinator of the math PhD program at UGA, and I've been doing everything I can to raise the rate of women students in the program and the lower the degree to which every woman currently in the program feels like an outsider.

Whenever issues of sexism in academia come up, those with direct experience with the situation and familiarity with the relevant literature find themselves interacting with people who have neither the academic nor the cultural expertise but nevertheless want to chime in. You haven't gone to mathoverflow.net to talk about Galois cohomology, but you have come to academia.SE expressly to weigh in on gender equality in American academia in a manner that does not even attempt to demonstrate or call upon any relevant expertise whatsoever. And you seem to think that's helpful. It's pretty weird.

@PeteL.Clark If you don't think that paragraph ending "The word mansplaining comes to mind" is a loud accusation of sexism I'd suggest you reread it in the morning. I don't doubt that your intentions are good, you're just being perhaps too "enthusiastic" in those intentions? Incidentally, I suspect Galois cohomology is sufficiently technically dense that the number of people able to talk about it is considerably fewer than those familiar with sexism. I hope your solution to dispute resolution isn't normally "I know topographic transforms, shut up!" :)

"I don't doubt that your intentions are good, you're just being perhaps too "enthusiastic" in those intentions?" I can send you literature and statistics that are in defense of a negative answer, if you like. If you just want to make jokes and broad, unjustified assertions, I will repeatedly respond in the same way until you get the point: this is a serious issue. Please be serious about it.