Weldon Leo "Jack" Teagarden (August 20, 1905 – January 15, 1964) was an American jazz trombonist and singer. According to critic Scott Yannow of Allmusic, Teagarden was the preeminent American jazz trombone player before the bebop era of the 1940s and "one of the best jazz singers too". Teagarden's early career was as a sideman with the likes of Paul Whiteman and lifelong friend Louis Armstrong.
Born in Vernon, Texas, United States, his brothers Charlie and Clois "Cub" and his sister Norma also became professional musicians. His father was an amateur brass band trumpeter and started him on baritone horn; by age seven he had switched to trombone. His first public performances were in movie theaters, where he accompanied his mother, a pianist.
In the late 1920s, he recorded with such bandleaders and sidemen as Armstrong, Benny Goodman, Bix Beiderbecke, Red Nichols, Jimmy McPartland, Mezz Mezzrow, Glenn Miller, and Eddie Condon. Miller and Teagarden collaborated to provide lyrics and a verse to Spencer Williams' "Basin Street Blues", which in that amended form became one of the numbers that Teagarden played until the end of his days.
Teagarden sought financial security during the Great Depression and signed an exclusive contract to play for the Paul Whiteman Orchestra from 1933 through 1938. In 1946, Teagarden joined Louis Armstrong's All Stars. In late 1951, Teagarden left to again lead his own band.