Octavia Irene Hall Smillie (August 30, 1889 – December 2, 1970) was an American dietitian.

She was chief dietitian at Peter Bent Brigham Hospital in Boston, and president of the American Dietetic Association from 1922 to 1924.

[3] She was elected to a two-year term as president of the American Dietetic Association in 1922, succeeding Mary deGarmo Bryan.

[8] In her later years, Smillie was active in the Massachusetts Dietetic Association,[9] trained Red Cross dietitian aides during World War II,[10] and traveled with her husband, an epidemiologist who established a school of public health in Brazil.

[11] In 1919, Octavia Hall became the second wife of widowed physician and Harvard Medical School professor Wilson George Smillie.