{{Short description|Ancient Roman and ecclesiastical rank}} {{About|the use of the term in the Roman and Byzantine empires|the various Western ecclesiastic and university offices|Dean (religion)|and|Dean (education)}}
'''''Decanus''''' means "chief of ten" in Late Latin. The term originated in the Roman army and became used thereafter for subaltern officials in the Byzantine Empire, as well as for various positions in the Church, whence derives the English title "dean". It is unrelated to the position of deacon (Latin ''diaconus'', Greek ''διάκονος'').
==History and functions== The ''decanus'' was originally the leader of a 10-man ''contubernium'', which consisted of the squad of eight legionaries who lived in the same tent, plus the two support units/servants of the contubernium.<ref>Vegetius. ''De Re Militari'' [http://www.thelatinlibrary.com/vegetius2.html 2.8.13].</ref> The title must not be confused with the ''decurio'', which was a title given to civic officials and to leaders of 30-strong squadrons (''turmae'') of cavalry. ''Decanus'' is equivalent to the rank of the ''dekarchos'' ("commander of ten") in Greek texts.
From the 4th century AD the term ''decanus'' became used for palace messengers, particularly those in the service of Roman empresses. ''Decani'' also apparently served as guards at gates, and in the 6th century, John Lydus equates them with the ancient lictors.<ref name="ODB">{{harvnb|Kazhdan|Cutler|1991|p= 601}}.</ref> In the 899 ''Klētorologion'' of Philotheos, the ''decanus'' (transcribed into Greek as δεκανός, '''''dekanos''''') was a mid-level functionary, serving under the ''protasekretis''. According to the mid-10th century ''De Ceremoniis'' of Emperor Constantine VII Porphyrogennetos ({{reign | 913 | 959}}), a ''decanus'' was "in charge of the imperial papers" when the Byzantine emperor was on campaign.<ref> {{harvnb|Bury|1911|p= 98}}. </ref> Sigillographic evidence for the Byzantine ''dekanoi'' is relatively rare, although some are depicted in illuminated manuscripts, where their appearance varies considerably, in accord with their varying and changing functions.<ref name="ODB"/>
In the Christian Church, the term came into use in monasteries for heads of groups of ten other monks, for low-ranking subaltern officials of the Patriarchate of Constantinople, and for the ecclesiastic ''fossores'' ("grave-diggers").<ref name="ODB"/>
==References== {{reflist|2}}
==Sources== * {{The Imperial Administrative System of the Ninth Century}} * {{Oxford Dictionary of Byzantium|last=Kazhdan|first=Alexander|authorlink=Alexander Kazhdan|last2=Cutler|first2=Anthony|title=Dekanos|page=601}}
Category:Ecclesiastical titles Category:Military ranks of ancient Rome Category:Byzantine palace offices {{italic title}}