Geoffrey Beene, who died yesterday at his Manhattan home at age 77,was the dean of American fashion designers. He helped define women’s fashion for more than 30 years, and was among the first to bring American design to Europe.

Among his characteristic looks were “baby doll” dresses of the 1960s and looser, unfitted lines starting in the 1970s, exemplified by his “Beene Bag” sportswear.

Throughout his career, his designs were renowned for their elegance and often for their simplicity. As his career matured, he became if anything more adventuresome, producing huge numbers of new designs each year in opulent fabrics.

Meanwhile, Beene’s business, which started with a simple Seventh Avenue showroom, grew into a multinational corporation with stores across America, factories in New York and in Europe, and licenses to other corporations that produced clothing and perfumes under his name.

Along the way, he dressed such women as Jacqueline Onassis, Gloria Vanderbilt Cooper, and Patricia Nixon, the first lady.

Son of an automobile salesman in rural Louisiana, Beene enrolled, unhappily, in the premed program at Tulane University. “The third year we got into vivisection, cadavers, and all that horrendous stuff,” Beene told Vogue in 1977. “And every disease we studied I got. “He amused himself during lectures by sketching the elaborate gowns the Hollywood designer Adrian designed for the 1943 film “Dubarry Was a Lady.”

Beene dropped out and headed for California, where he found work at the downtown Los Angeles branch of I. Magnin, a fashionable clothing chain. An executive noted Beene’s flair for arranging displays and advised him to get into the fashion business. Beene headed for New York.

After studying at the Traphagen School of Fashion in Manhattan, he went to Paris to work on sketching and sewing in couture houses. Returning to New York in 1949, Beene found work as a designer for the custom salon Samuel Winston, and then for Harmay. A 1955 sketch from the New York Times shows two of his Harmay designs, “transition dresses to bridge the gap between summer and autumn,” which would have looked nice on Grace Kelly. The patterns were available via mail-order for 50 cents.

Having partnered with Teal Traina in 1958, Beene’s 1961 summer line caused a sensation in New York fashion with a flaring, knee-baring skirt.

In 1963, Beene partnered with Traina’s former production manager to start his own business, and unveiled a champagne-colored showroom on Seventh Avenue, in the heart of the garment district. His first collection, priced between $90 and $375, quickly sold to buyers at Bergdorf Goodman, Saks Fifth Avenue, and Henri Bendel. Within four years, sales had quadrupled, to more than $2 million.

By 1967,his spring line included high waisted “little girl” dresses, short “rice paddy” pants, harem pyjamas, and a host of elegant accessories. In what seemed like a stunt, he had a football jersey sent to Paris, where it was lengthened, beaded, and turned into an evening dress. That same year, he designed the wedding dress for Lynda Bird Johnson, daughter of the president.

Beene began designing menswear in 1969. Films of the 1930s and 1940s had a marked influence on the clothes, although he refused to produce tuxedoes, which he considered constricting.

Freedom was more than ever his byword in the early 1970s, as his designs became freed from traditional strictures.

While manufacturing clothes in Eu rope, he experimented with franchising jewelry, scarves, eyeglass frames, panty hose, loungewear, and linens. Eventually, though, he settled on men’s shirts and perfumes as the most profitable. In 1990, he opened his first shop, at the Sherry-Netherlander Hotel on Fifth Avenue.

Beene liked to entertain at his Upper East Side duplex and at his weekend home at Oyster Bay, where he grew orchids in profusion. He collected surrealism and art deco, and traveled to Europe regularly to find new fabrics.

After leading hemlines up through the 1960s, back down in the 1970s, and then back up in the 1980s, Beene in 1988 pronounced himself indifferent to skirt length. “Trends are going to be less important in women’s clothes because they are not really necessary,” he predicted. “Fashion should be beautiful, not necessarily newsworthy. Changes should evolve slowly. I have never admired revolutionary changes.”

He received fashion’s highest awards, including eight Coty Fashion Critics Awards, and his clothes are in the collections of many museums, including the Fashion Institute at the Metropolitan.

Geoffrey Beene

Born August 30, 1927, at Haynesville, La.; died September 27 at his home in Manhattan, of pneumonia; survived by a sister, Barbara Ann Wellman of Texas.