Geary, an Anglicized rendering of the Irish name O'Gadhra, has a number of meanings:
Geary as a surname:
- Anthony Geary (1947– ), an American actor
- Benjamin Handley Geary (1891–1976), a British soldier in World War I and a recipient of the Victoria Cross
- Bob Geary (police officer), a former San Francisco police officer best known for his ventriloquist's dummy, Brendan O'Smarty
- Cynthia Geary, American actress probably best known for Northern Exposure
- David C. Geary, an American academic psychologist
- Sir Francis Geary, 1st Baronet (1709-1796), Royal Navy admiral
- Francis Geary (1752–1776), a British officer (and son of Admiral Francis Geary) killed in the Ambush of Geary during the American Revolutionary War
- Geoff Geary (1976– ), an American Major League Baseball player, relief pitcher, currently with the Philadelphia Phillies
- George Geary (1893–1981) England cricketer
- George Reginald Geary (1873–1954), mayor of Toronto, Ontario, Canada from 1910 to 1912
- James Geary, London-based editor of Time magazine and author of The Body Electric.
- John W. Geary (1819–1873), mayor of San Francisco, governor of the Kansas Territory, governor of Pennsylvania and general in the American Civil War
- Joseph Geary, New York Times bestselling author
- Roy C. Geary, (1896-1983), Irish social scientist
- Thomas J. Geary, (1854-1929), U.S. Representative from California.
Geary as a place:
- Geary County, Kansas
- Geary, Oklahoma
- Geary, Isle of Skye
- Geary, New Brunswick
- Geary Boulevard, a major thoroughfare in San Francisco, California
Geary can also refer to:
- Geary Act, an 1892 U.S. government law that restricted the rights of Chinese immigrants in the United States
- Geary baronets, a baronetcy in the baronetage of Great Britain
- D. L. Geary Brewing Company, a microbrewery located in Portland, Maine.
- Pat Geary, a fictional character in the film The Godfather, Part II
- Roy Geary, a fictional character from the television show Prison Break