What does the term 'paterfamilias' mean?

The '''''pater familias''''', also written as '''''paterfamilias''''' (plural ''patres familias'') was the head of a Roman family. The term is Latin for "father of the family" or the "owner of the family estate". The form is irregular and archaic in Latin, preserving the old genitive ending in ''-as'' (see Latin declension). The ''pater familias'' was always a Roman citizen.