A vicar is a representative, deputy or substitute; anyone acting “in the person of” or agent for a superior. Linguistically, vicar is cognate with the English prefix “vice“, similarly meaning “deputy”. It also refers to a senior priest in the Church of England. The title appears in a number of Christian ecclesiastical contexts, but also as an administrative title, or title modifier, in the Roman Empire. In addition, in the Holy Roman Empire, a local representative of the emperor, such as an archduke, could be styled “vicar”
The title is very old and arises from the medieval arrangement where priests were appointed either by a secular lord, by a bishop or by a religious foundation. Historically, but no longer, vicars share a benefice with a rector (often non-resident) to whom the great tithes were paid. Vicar derives from the Latin vicarius meaning a substitute. https://en.wikipedia.org/wiki/Vicar_(Anglicanism)?wprov=sfti1#
Etymology
Parish churches in England originated as the personal property of (predominantly lay) patrons, who had the right to appoint and dismiss the parish priest, to receive an entrance fee on appointment, and to charge an annual rent thereafter. Knowles, David The Monastic Order in England Cambridge University Press, 1940, p.593
vicar (n.)
early 14c., from Anglo-French vicare, Old French vicaire “deputy, second in command,” also in the ecclesiastical sense (12c.), from Latin vicarius “a substitute, deputy, proxy,” noun use of adjective vicarius “substituted, delegated,” from vicis “change, interchange, succession; a place, position” (from PIE root *weik- (2) “to bend, to wind”). The original notion is of “earthly representative of God or Christ;” but also used in sense of “person acting as parish priest in place of a real parson” (early 14c.). https://www.etymonline.com/word/vicar
Additional reading:
Dogmatic Constitution On The Church
Lumen Gentium
Solemnly Promulgated By His Holiness
Pope Paul Vi
On November 21, 1964:
https://www.vatican.va/archive/
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