What does caput mean?
Caput is a noun borrowed directly from Latin, where it means 'head'. In modern English it survives in two specialised senses. In law and legal history, a caput is a distinct section, paragraph, or numbered division of a formal document such as a statute, charter, or papal bull; scholars may refer, for example, to 'the third caput' of a medieval text. In anatomy and medicine, caput denotes the rounded head of a bone — most famously the caput of the femur — which fits into a socket to form a joint. The word's plural, capita, will be familiar to almost everyone through the phrase 'per capita', meaning 'per person', a usage rooted in ancient practice: Romans counted populations by heads. Because both its senses are confined to technical registers, caput is rarely encountered in ordinary conversation, yet its legacy permeates English through related words like capital, captain, and chapter, all descended from the same Latin root.
A distinct section or numbered division of a legal or ecclesiastical document.
"The privilege was confirmed in the second caput of the charter."
Chiefly used by historians and lawyers discussing older statutes, charters, and canon law texts.
In anatomy, the rounded head of a bone that forms part of a joint.
"Fractures of the radial caput can restrict forearm rotation."
The plural capita follows the standard Latin pattern and is best known today from the fixed phrase 'per capita'.
"The country spends more per capita on healthcare than its neighbours."
Every time you say 'per capita', you're using the plural of caput — Latin for 'head', because in Roman counting, people were counted by their heads.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of caput
Caput was taken directly from Latin, where it means 'head'. It entered English scholarly vocabulary during the medieval and early modern periods, when legal and theological texts were studied in Latin and terms were adopted wholesale rather than translated. It shares its Indo-European root *kaput- ('head') with many common English words, including capital, captain, chapter, cattle, and decapitate, most of which arrived via Old French from the same Latin source.
How caput is actually used
Both senses are technical and rare outside specialist contexts: the documentary sense appears chiefly in legal history and canon law, while the anatomical sense is used mainly in medicine, often as 'caput' of the femur, humerus, or radius. In everyday English the word survives mostly in the plural within the phrase 'per capita'.
Easily confused with caput
Capital is an adjective meaning chief or excellent, a noun meaning wealth or a city, while caput is the Latin-derived noun for a section of a document or a bony head of a joint.
Capita is simply the plural of caput, most familiar in the phrase 'per capita', whereas caput is the singular form.