American-born Irish author of the comic novel The Ginger Man (Paris, 1955; U.S., 1958), which introduced Dangerfield, a crass, comic antihero. Donleavy's works are noted for their coarse sense of humour and for characters who remain deeply attached to life despite its flaws.

Donleavy served with the U.S. Navy during World War II, studied microbiology at Trinity College, Dublin, and became an Irish citizen in 1967. His works are distinguished by an original treatment of voice, in which action occurs in the third person while thoughts are conveyed in the first, allowing the character to speak both as observer and observed. A Singular Man (1963), The Saddest Summer of Samuel S. (1966), The Onion Eaters (1971), A Fairy Tale of New York (1973), and later works continued to develop the alliterative prose style of The Ginger Man. His trilogy about the misadventures of an Irish vagabond began with The Destinies of Darcy Dancer, Gentleman (1977) and continued with Leila: Further in the Life and Destinies of Darcy Dancer, Gentleman (1983) and That Darcy, That Dancer, That Gentleman (1990). The story of Schultz (1979) continued in Are You Listening, Rabbi Löw (1987), which chronicles Schultz's incessant trials with women and money and was widely criticized for its vulgarity and use of derogatory Jewish and female stereotypes. The Lady Who Liked Clean Restrooms (1997) is a satirical tale of a depressed, formerly wealthy middle-aged woman obsessed with propriety. Wrong Information Is Being Given Out at Princeton (1998) is the story of a feckless aspiring composer.

Donleavy's other works include A Singular Country (1989), a humorous and biting critique of modern Ireland, and The History of the Ginger Man (1994), which chronicles, with characteristic exaggeration, the challenges of writing and publishing his most famous novel.