Clarissa is a female given name borrowed from Latin, Italian, and Portuguese,^[1] originally denoting a nun of the Roman Catholic Order of St. Clare. It is a combination of St. Clare of Assisi's Latin name Clara (originally meaning "clear" and "bright") and the suffix -issa, equivalent to -ess. Clarice is an anglicization of Clarisse, the French form of the same name. Clarisa is the Spanish form of the name,^[1] and Klárisza the Hungarian.^[2] The given names Clara, Clare, and Claire are all cognates, as are the surnames Sinclair and St. Clair.

• Clara Barton (Clarissa Harlowe Barton, 1821–1912), American humanitarian who founded the American Red Cross
• Clarissa Britain (1816–1895), American inventor
• Clarissa Davis (born 1967), American coach and women's basketball hall-of-famer
• Clarissa Dickson Wright (1947–2014), English celebrity chef
• Clarissa F. Dye (1832–1921), Civil War nurse from Philadelphia
• Clarissa Eden, Countess of Avon (1920–2021)
• Clarissa Pinkola Estés (born 1945), American writer and Jungian psychoanalyst
• Clarissa Caldwell Lathrop (1847–1892), American social reformer, autobiographer
• Clarissa Kaye (1931–1994), Australian stage, film and television actress
• Clarissa Ward (born 1980), British-American television journalist
• Clarissa Stadler (born 1966), Austrian journalist, moderator and writer

• Clarissa Explains It All, a children's TV show in the 1990s
• Clarissa Dalloway in Mrs Dalloway, a 1925 novel by Virginia Woolf
• Clarissa "Clary" Fray in The Mortal Instruments novel series
• Clarissa Harlowe, the heroine of Samuel Richardson's 1748 tragic epistolary novel Clarissa, or, the History of a Young Lady
• Clarissa Hailsham-Brown in Spider's Web, a 1954 play by Agatha Christie
• Clarissa Mellon in Enduring Love, a 1997 novel by Ian McEwan
• Clarissa Saunders in Mr. Smith Goes to Washington, a 1939 film

• Clarissa (disambiguation)
• Poor Clares, nuns of the Order of St Clare, also called the Clarissas or Clarisses
• Claire (given name)
• Clara (given name)
• Clare (given name)
• Clarice