Lucy Clifford (2 August 1846 – 21 April 1929), better known as Mrs. W. K. Clifford, was a British novelist and journalist, and the wife of William Kingdon Clifford.
Lucy Clifford was born Lucy Lane in London, the daughter of John Lane of Barbados. She married the mathematician and philosopher William Kingdon Clifford in 1875. After his death in 1879, she earned a prominent place in English literary life as a novelist, and later as a dramatist. Her best-known story, Mrs Keith's Crime (1885), was followed by several other volumes, such as Aunt Anne (1892). She also wrote The Last Touches and Other Stories (1892) and Mere Stories (1896); and a play, A Woman Alone (1898). She is perhaps most often remembered, however, as the author of The Anyhow Stories, Moral and Otherwise (1882), a collection of stories written for her children.
Lucy Clifford also wrote cinematic adaptations of her short stories and plays. At least two films were produced from her adaptations: The Likeness of the Night (1922) directed by Percy Nash, and Eve's Lover (1925) directed by Roy Del Ruth.
She had a wide circle of literary friends, amongst them Henry James. Her daughter Ethel Clifford (d. 1959), later Lady Dilke, having married Sir Fisher Wentworth Dilke, 4th Baronet (1877–1944) in 1905, was a published poet.
Lucy Lane Clifford died in 1929, and was buried alongside her husband in Highgate Cemetery in London.
In 2004 Gowan Dawson described Lucy's efforts to uphold the reputation of Clifford after his death:
- ...Clifford's disconsolate widow and two young daughters had been left totally unprovided for, and, notwithstanding a subsequent Testimonial Fund and Civil List pension, it was necessary for Lucy Clifford, who now owned the copyright of her late husband's works, to maximize the potential sales of his posthumous publications by not only by keeping Clifford in the public eye, but also by ensuring that it was a generally positive (and thus marketable) portrayal of him that was presented.
Selected writings 
- Clifford, Lucy (1885). Mrs. Keith's Crime. London: Richard Bentley & Son.
- Clifford, Lucy (1885). The Anyhow Stories. London: Macmillan & Company.
- Clifford, Lucy (1892). Aunt Anne. New York: Harper & Brothers.
- Clifford, Lucy (1892). Love Letters of a Worldly Woman. Philadelphia: Harper & Brothers.
- Clifford, Lucy (1892). The Last Touches and Other Stories. Archived from the original on 2009-10-26.
- Clifford, Lucy (1896). A Flash of Summer: The Story of a Simple Woman's Life. New York: D. Appleton and Company.
- Clifford, Lucy (1896). Mere Stories. London: A. and C. Black. Archived from the original on 2009-10-26.
- Clifford, Lucy (1897). The Dominant Note and Other Stories. New York: Dodd, Meade and Company.
- Clifford, Lucy (1902). A Long Duel: A Serious Comedy. London and New York: John Lane.
- Clifford, Lucy (1902). Woodside Farm. London: Duckworth and Company.
- Clifford, Lucy (1904). The Getting Well of Dorothy. London: Methuen and Company.
- Clifford, Lucy (1910). Plays. New York: Mitchell Kennerley.
- Clifford, Lucy (1915). A Woman Alone. New York: Charles Scribner's Sons. Archived from the original on 2009-10-26.
- Clifford, Lucy (1919). Miss Fingal. New York: Charles Scribner's Sons.
- Chisholm, M. (2002). Such Silver Currents. Cambridge: The Lutterworth Press. p. 8. ISBN 0-7188-3017-2.
- Gowan Dawson (2004) "Victorian periodicals and the making of William Kingdon Clifford's posthumous reputation", pages 259 to 284 in Science Serialized, Geoffrey Candor & Sally Shuttleworth editors, MIT Press ISBN 0-262-03318-6 .
- William and Lucy Clifford
- Biography of Lucy Clifford by Monty Chisholm
- A guide to the Mrs. W. K. Clifford Papers at the Beinecke Rare Book and Manuscript Library