encephalo

Encephalo- is a combining form used in medical terminology to denote a relation to the brain. It derives from the Greek enkephalos, meaning “in the head” or “brain,” and is part of the larger family of encephal- terms used in neurology and anatomy.

The form appears in many terms that describe brain structure or brain-related conditions, such as encephalitis (inflammation of the brain), encephalopathy (disease or dysfunction of the brain), encephalography (imaging of the brain), encephalomalacia (softening of brain tissue), and encephalotomy (surgical interruption of brain connections). The noun encephalon refers to the brain itself as an anatomical term.

In practice, encephalo- and encephal- are variants of the same combining form; the choice between them depends on etymology and phonology, as well as the suffix attached. The form functions as a prefix or combining form in compound terms rather than as an independent word.

See also: neuro-, brain, cranial, encephalitis.