American singer and motion-picture actress whose performances in movie musicals of the 1950s and sex comedies of the early '60s made her a leading Hollywood star.

While still a teenager, she changed her last name to Day when she began singing on radio. She worked as a vocalist in the bands of Barney Rapp and Bob Crosby before joining Les Brown's band in 1940 and making several popular recordings, among them “Sentimental Journey.” Day went solo in 1947 and achieved great success as a recording artist. Her singing was distinguished by crystal-clear tone and the ability to convey great emotion without histrionics.

Day's first major film role was in Romance on the High Seas (1948). From there she made a long series of musicals, including Calamity Jane (1953), Young at Heart (1955), Love Me or Leave Me (1955), and The Pajama Game (1957). Her screen persona, that of an intelligent, wholesome woman of unfailing optimism and understated strength of character, came to epitomize the ideal American woman of the 1950s. Day went on to star in a string of sophisticated sex comedies, notably Teacher's Pet (1958), Pillow Talk (1959), Lover Come Back (1962), That Touch of Mink (1962), The Thrill of It All (1963), and Send Me No Flowers (1964). These comedies made her Hollywood's leading box-office attraction. From 1968 to 1973 she starred in The Doris Day Show, a weekly television series.

As her acting career neared its end, Day focused her attention on animals (animal rights), cofounding Actors and Others for Animals. In 1977 she founded the Doris Day Pet Foundation, and ten years later she became a founding member and president of the Doris Day Animal League, a lobbying organization for laws regulating the treatment of animals.