Mildred Sarah Ginn Uhl, 84, whose name was used when the office supply firm of M.S. Ginn and Company was established here in 1926, died Wednesday at the Bethesda Retirement and Nursing Center in Chevy Chase, where she had lived since last October. She had arteriosclerosis.

Mrs. Uhl, then Miss Ginn, was working as a secretary of the Washington School for Secretaries when five businessmen affiliated with the school started a small shop to sell supplies to the students, according to a history of the Ginn firm.

Since it would have been too cumbersome to include the names of all five founders in the name of the store, the partners decided to use the name of Miss Ginn. According to the company history, they thought the Ginn name was "short and pert and ideal for promotions and advertising."

Miss Ginn herself worked only briefly for the new company, but her name remained. Ginn's went on to become one of the largest office supply firms in the country.

Mrs. Uhl was born in Sidney, Ohio. She came to Washington in 1918. In 1929, she married Harry Grant Uhl, an executive with the National Lumber Manufacturers Association. He died here in 1966.

Mrs. Uhl was a member of the National Presbyterian Church and had served as president of its Women's Association. She was a member of the Women's Board of the National Presbyterian Home. She was a former member of the Washington Club and the Chevy Chase Woman's Club.

She is survived by a son, Grant S. Uhl of Bethesda, and three grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to a charity of one's choice.