On a man, a tailored jacket and matching pants are called a “suit.” Put these same garments on a woman, though, and they transform into a “pantsuit.”

Because of the presidential campaign of Hillary Clinton, self-proclaimed “pantsuit aficionado,” the term pantsuit—and the garment itself—have been everywhere. To many, the distinction between a suit and pantsuit smacks of sexism. It arguably turns women into the other, the non-standard case. While a “suit” connotes power and authority, a “pantsuit” suggests a lesser form that pretends to being a suit, leading to an understandable dislike. But that dislike is telling. It reflects the ongoing shift in a woman’s role in society.

The term pantsuit dates back to at least the 1860s, when it didn’t refer to women’s clothing at all. According a brief history by Merriam-Webster, “in its first incarnation, the pantsuit was worn by young boys. The earliest record we have of the word being used in English occurs in 1865, in an advertisement from a newspaper in Bloomington, Indiana, The Pantagraph: ‘Double Shawls, Gents’ and Boys’ Cloths for coats and pants suits.'”

Peter Sokolowski, a lexicographer at Merriam-Webster, says it was presumably used to distinguish a suit with full-length trousers from those with the short pants boys typically wore in that era. It took about a century before the word came to refer to women’s clothes. “The first reference to pantsuit specifically for women dates to 1959 in an advertisement,” he says, and the term apparently maintained its function. It differentiated between a suit worn with pants, versus a skirt.

Though Coco Chanel popularized a woman’s suit that included a jacket tailored like a man’s in the 1920s, a skirt made up the bottom portion. Pants were not ladylike at the time. The first pantsuits, such as the tuxedo Marlene Dietrich wore in the 1930 film Morocco, or the style introduced in 1932 by French designer Marcel Rochas, were sensational. That sentiment didn’t change until the 1960s, after women entering the workforce in the postwar years started adopting suits. Still, a suit with a skirt was the standard, and pants were the alternative choice—hence the “pantsuit.”

Thanks in part to Yves Saint Laurent and the 1970s, pantsuits are now a staple of the working woman’s closet—a symbolism Clinton plays into with her rotating wardrobe of them. Clinton’s pantsuits are still arguably fighting for equality, however.

If you’re a man, and you’re running for president, you wear a suit. It’s the standard option—really the only option. No item of women’s clothing plays the same role—just look at Clinton’s wardrobe against that of the UK’s sartorially flexible prime minister, Theresa May. The situation opens women up to more scrutiny: We speculate about what they mean to say with their outfits. (It’s no wonder Clinton has reportedly tapped Vogue’s Anna Wintour to consult on her wardrobe.)

The lack of consistency also means that, when standing beside men in suits, women are always wearing the “non-standard” option. Linguist Deborah Tannen likened this situation, and many other women face, to the “marked” case in language in a 1993 essay (pdf) for the New York Times Magazine. You mark a word to indicate a deviation from its main usage, such as adding “-ed” to signify past tense, or “-ette” to identify it as feminine, since male is the unmarked standard—just as the men’s suit is in professional attire.

“I asked myself what style we women could have adopted that would have been unmarked, like the men’s,” Tannen wrote. “The answer was none. There is no unmarked woman.”