A dinner dress really means every sort of low, or half low evening dress.
A formal dinner dress, like a ball dress, is always low-necked and without
sleeves, and is the handsomest type of evening dress that there is. A ball
dress may be exquisite in detail but it is often merely effective. The
perfect ball dress is one purposely designed with a skirt that is becoming
when dancing. A long wrapped type of dress would make Diana herself look
like a toy monkey-on-a-stick, but might be dignified and beautiful at a
dinner. A dinner dress differs from a ball dress in little except that it
is not necessarily designed for freedom of movement.

Hair ornaments always look well at a ball but are not especially
appropriate (unless universally in fashion) on other occasions. A lady in
a ball dress with nothing added to the head, looks a little like being
hatless in the street. This sounds like a contradiction of the criticism
of the vulgarian. But because a tiara is beautiful at a ball, or a spray
of feathers, or a high comb, or another ornament, does not mean that all
of these should be put on together and worn in a restaurant; which is just
what the vulgarian would do. Whether, to wear a head-dress, however,
depends not alone upon fashion but upon the individual. If the type of
hair ornament at the moment in fashion is becoming, wear it, especially to
balls and in a box at the opera. But if it is not becoming, don't.

Ladies of fashion, by the way, do not have their hair especially dressed
for formal occasions. Each wears her hair a certain way, and it is put up
every morning just as carefully as for a ball. The only time it is
arranged differently is for riding. Ah informal dinner dress is merely a
modified formal one. It is low in front and high in the back, with long or
elbow sleeves--or perhaps it is Dutch neck and no sleeves.

When trains are in fashion, all older women should wear them. Fashion or
no fashion, no woman who has passed forty looks really well in a cut-off
evening dress. An effect of train, however, can very adequately be
produced with any arrangement or trimming that extends upon the floor.

The informal dinner dress is worn to the theater, the restaurant (of high
class), the concert and the opera. Informal dinner dresses are worn in the
boxes at the opera on ordinary nights, such as when no especially great
star is to sing, and when one is not going on to a ball afterward, but a
ball dress is never inappropri