Ada Leverson (1862-August 1933), nee Beddington, was a British writer, now known as a novelist.
She began writing during the 1890s, as a contributor to Black and White, Punch, and The Yellow Book. She was a loyal friend to Oscar Wilde, who called her Sphinx; in the 1997 film Wilde she is played by Zoe Wanamaker. She was a wit, and a friend of Max Beerbohm; her writing has been compared to Beerbohm's, and the stories of Saki.
She was also a friend of George Moore; Osbert Sitwell in Great Morning has an anecdote in which she tries, unsuccessfully, to get Moore to see the young William Walton. Of the Sitwells' circle — Sacheverall Sitwell dedicated a poetry collection to her, while she was hopelessly in love with Osbert — she lived out her old age in the Hotel Porta Rossa in Florence.
She married Ernest Leverson, when she was 19, and without her parents' consent. The marriage broke up when he moved to Canada in 1905. Her daughter and biographer Violet married Guy Percy Wyndham (1865-1941) in 1923, his second marriage.
Sydney Schiff was her brother-in-law.