Keep Your Pants On
That garment likely covering your legs is named for a creepy old man common in European theater a few centuries back. Crafty, greedy “Pantalone,” whose schemes often failed and led to his humiliation, was a stock character in plays from the 16th-18th centuries. Early on, he typically wore breeches and red stockings, but in later years wore long trousers. When similarly-styled trousers caught on outside the theater, they were called “Pantaloons” in England, which eventually got shortened to just “pants, ” which is part of “underpants” and “panties.”
With far less instrumentation, early pilots had to rely much more on their own senses more to fly. Their rear end had some of the most direct contact with the plane, from which they could feel engine vibration, angle, and other input. This is why flying intuitively with little or no input from instruments and radios came to be known as “flying by the seat of your pants.”
The association with the person who “wears the pants in the family” (or trousers of you’re British) being the family decision-maker it is simply based on the fact that only men historically wore pants and also traditionally had that role.
Saying “denim jeans” invokes the names of two cities which are part of the garment’s origin story. The strong fabric originally made in de Nimes, France, was called “Serge de Nimes,” but Genoa, Italy, also played a role in the development of the garment, and has used the term “bleu de Genes” (blue material from Genoa) for the fabric which has clad their fisherman for five centuries now.
The first known usage of the term “fancy pants” was not to describe a fancy or pretentious person, but just actual fancy pants. The term first appeared in a Bangor, Maine newspaper advertisement in the 1840s for pants made of Cassimere, or wollen twill fabric. About 90 years later, the term began to have its current connotation.
Women wearing pants in public was not a widely accepted fashion until the late-mid 20th century. From “bloomers” to “harem pants,” many designers introduced the two-legged garment for women before that, but it didn’t really catch on until the 1960s and ’70s.
The innovation which made jeans so successful after their patenting in 1873 was reinforcing metal rivets placed at the stress points such as the corners of pockets. Jacob Davis, a tailor and later business partner of Levi Strauss, had this idea when tasked with creating a highly durable pair of pants for a local laborer. The jeans were a hit with Western miners and other laborers during the California Gold Rush, who needed durable clothing for their work.