[Literide]

The military equivelent of semi-formal is mess dress which is either a class A or formal uniform worn with a black bow tie.

Why is eveyone trying to divine the hosts intent?

The intent is clear, (evening, semi-formal) so why not just do what the invitation says and wear black tie.

 

[Literide]

In the U.S. Navy and I think the Royal Navy also, mess dress is equivalent to white tie while mess undress is the black tie equivalent.

Probably because most think that isn't what the hosts mean, despite the wording. In the U.S. very few people would interpret semi-formal to mean black tie. The issue isn't who is right or wrong, but what is the most appropriate thing to do when it's someone else's wedding.

My fear would be that my showing up in a tuxedo would be embarrassing to the hosts if everyone else is in a suit because I would then be compelled to explain the meaning of semi-formal to people (because they are going to ask about the tuxedo) which would make the hosts look like they didn't know what they were doing. And even if they didn't know what they were doing when they said semi-formal, I would not want to publicly embarrass them this way by drawing attention to their lack of sartorial knowledge.

The best thing to do is to try to find out exactly what is being requested. If I couldn't find out ahead of time I would wear a suit because that is what most will wear even if the hosts mean black tie. I would much rather be wrong this way than to risk being the only person in a tuxedo at someone else's wedding.

Cruiser

You may be right on the mess dress/undress distinction in which case military people attending would be wearing mess undress to the wedding while others would wear civilian black tie. That is assuming the hosts knew what they were doing when they indicated semi-formal. As the bride is purported to be a well bred lady and I assume she is marrying an officer, they probably understand the traditional intent of semi-formal.

As it seems at least one guest and many forumites are still trying to divine some other intent based on some all to common misconceptions, an email or phone call is surely in order.

Cheers

 

[Literide]

Over the past 60 years I have lived in Beaufort, South Carolina; Nashville, Tennessee; and Jacksonville, Florida; in addition to spending a considerable amount of time in Atlanta, Georgia. The majority of guys that I know do not own tuxedos and I have routinely seen semi-formal interpreted to mean a suit. I can only assume that you hang with a very select group of people, but they certainly aren't the norm.

Please don't get me wrong, I'm not saying that the invitation doesn't mean black tie. I'm just saying that based on my personal experiences I would not interpret it that way. And like I said, I am very familiar with the South East.

Cruiser

A suit would be
Business attire (US)
Lounge suit (UK)

 

[Literide]

If no response from the host or reliable close friends of the host, wear a dark suit.

I recently attended what ought to be a very formal event. The invitation specified semi-formal. Hoping that they meant black tie, but not holding my breath, I asked the organizer if this was the case.

"Oh, no. Well, maybe it used to mean black tie, but now that would be very formal. Semi-formal for this event means khaki pants with a shirt. And maybe a tie."

Ugh. Thankfully, few (if any) others asked her to clarify and most were in black tie and almost all the rest in dark suits.

pbc

See what happens when people start inventing their own definitions rather than consulting an authoritative etiquette guide. Or simply being specific ie "Blazer or jacket and tie requested", or "shirt required, tie optional". The latter approach cuts the ambiguity and helps the uninitiated not embarass themselves.