Clifford

Clifford is a name of English origin used as both a surname and a given name. It derives from the toponym Clifford, from Old English elements meaning “cliff” or “slope” and “ford” or “passing place,” describing a person from a ford by a cliff. The name has appeared in literature, science, and public life, and is associated with various places and institutions named Clifford.

In popular culture, Clifford the Big Red Dog is a children’s book series created by Norman Bridwell in 1963. The stories follow Clifford, a giant red dog adopted by a girl named Emily Elizabeth, and they have expanded into animated television series, films, and a wide range of merchandise. Notable adaptations include a PBS Kids animated series and a 2021 feature film, Clifford the Big Red Dog, released by Paramount Pictures.

In mathematics, Clifford algebra is named after William Kingdon Clifford (1845–1879), an English mathematician who developed a system of geometric algebra. It generalizes complex numbers and quaternions and underpins modern approaches to geometry used in physics, computer graphics, and robotics. The field also includes the Clifford group and concepts such as spinors.

William Kingdon Clifford was educated at University College London and Trinity College Cambridge; his work influenced later developments in algebra, geometry, and theoretical physics.