Here at wiseGEEK, we never let a little phrase such as "origin unknown" stand in our way. Such is the case with the origin of the term dressed to the nines. Reference after reference failed to turn up a definitive origin for the expression, although they all seem to agree on its meaning. Describing someone as being "dressed to the nines" implies the donning of expensive clothing, jewelry and other fashionable accessories, most likely for a formal dance or theatrical performance.

One prevailing theory concerning the origin of "dressed to the nines" surrounds the significance of the number nine. Some sources believe that the number 9 possessed a spiritual or cultural strength, much like the numbers 3,7 or 13 do today. For example, there were nine Muses said to inspire mankind's pursuit of the arts. If someone were described as "dressed to the nines", it could have been an outfit capable of impressing the nine Muses. The expression "to the nines" was actually in popular use before "dressed to the nines" came into vogue. It's entirely possible that the reference was meant as a tribute to the Muses or other significant figures.

Another theory states that women of the Middle Ages would often wear fashionable gloves as part of their formal wear. These gloves were said to contain nine buttons from wrist to elbow, so if a woman was said to be "dressed to the nines", she would be wearing her most formal evening wear. In a similar vein, the price for admission for theatrical performances often ranged from one shilling for a front row seat to nine shillings for the preferred balcony or box seating. Anyone who could afford the highest ticket prices might be considered "dressed to the nines" as opposed to the unwashed groundlings seated on the grass in front of the stage.

Some sources believe that the expression "dressed to the nines" is somehow related to the expression "the whole nine yards." Each was once thought to originate in the tailoring profession, where it was believed that a quality suit or gown required nine yards of material. In reality, most tailors and dressmakers could create very elegant clothing from far less material. The "whole nine yards" may have been inspired by the 27 feet (or nine yards) of cloth used in a military gun belt, but no one has been able to connect "dressed to the nines" with the expression "whole nine yards."

There is even a theory which suggest "dressed to the nines" may have been corrupted from "dressed to the eyes", an expression which also means the donning of elegant formal-wear. It is possible that the original expression morphed from the eyes into the nines in the same way a narancia, the original name of the citrus fruit, became slurred as an arancia. We now say "an orange" even though the original word began with an "n", so it is possible that we say "dressed to the nines" instead of the original "dressed to the eyes." Anything is possible whenever dictionaries throw down the etymological gauntlet known as "origin unknown."