Rear Adm. Grace Murray Hopper, a pioneer Navy computer programmer and co-inventor of the business language COBOL, has died, her brother said Thursday. The 85-year-old admiral -- at the time of her retirement in 1986 the nation's oldest active-duty military officer -- died Wednesday in her Arlington, Va., home, said her brother, Roger F. Murray II of Wolfsboro, N.H. Admiral Hopper, known to her aides as "the first lady of software" and "Amazing Grace," stayed in uniform under year-to-year extensions long after the regular retirement age of 62 to work on the Navy's computer programs. "She has challenged at every turn the dictates of a mindless bureaucracy," former Navy Secretary John Lehman said when he awarded her the Defense Department's highest honor, the Defense Distinguished Service Medal for exceptional meritorious service. Admiral Hopper, who held a doctoral degree in mathematics from Yale University, joined the Naval Reserve in December 1943 after a decade of teaching at Vassar College and midshipman training at Smith College. She was soon to report for duty to a basement laboratory at Harvard University, where she worked on equipment designed to figure ordnance calculations. There, she learned to program the first large-scale digital computer, the Mark I. After the war, she remained in the Naval Reserve and joined a company that was building the Univac I, the first commercial, large-scale electronic computer. The company later merged into the Sperry Corp. At Sperry, she worked on an idea that led to COBOL, a widely used programming language. She was also credited with coining the word "bug" to describe the problems that plague computers and their programs.