For men, semi-formal attire means wearing a full suit, with vest optional. A tie, either bow or straight, should be worn, and the shirt should be a simple button down.
In the modern sense, a tuxedo is considered formal attire.
As with men's clothing, women's outfits for a semi-formal event should be relatively conservative, and avoid showing too much leg or cleavage. Hem lenghths vary, but dresses or skirts should end no more than one inch above the knee. Longer skirts with a dressy top can be appropriate. Tops should not be cut too low or be too revealing. Strapless tops or dresses can be acceptable choices provided they aren't too skimpy.
Floor lenghth dresses are considered formal attire.
For more information, contact RFHS administration.