Chancellor
late Old English from Old French cancelier, from late Latin cancellarius ‘porter, secretary’ (originally a court official stationed at the grating separating public from judges), from cancelli ‘crossbars’.
wiktionary
From Anglo-Norman or Middle English chaunceler, chanceler, canceler(“chief administrative or executive officer of a ruler; chancellor, secretary; private secretary, scribe; Lord Chancellor of England; officer of the ruler's exchequer; a high administrative or executive officer (for example, a deputy or representative of a bishop; the head of a university)”), from Old French cancelier, chancelier(“chancellor”), [1] from Late Latin cancellārius(“secretary; doorkeeper, porter; usher of a court of law stationed at the bars separating the public from the judges”), [2] from Latin cancellī ( plural of cancellus(“grate; bars, barrier; railings”), diminutive of cancer(“grid; barrier”), from Proto-Italic *karkros(“enclosure”), ultimately from Proto-Indo-European *(s)ker-(“to bend, turn”)) + -ārius(suffix forming nouns denoting an agent of use).
The word was present as Late Old English canceler, cancheler, from Norman cancheler, but was displaced in the 13th century by the Old French and Anglo-Norman forms mentioned above. [2]
etymonline
chancellor (n.)
early 12c., from Old French chancelier (12c.), from Late Latin cancellarius "keeper of the barrier, secretary, usher of a law court," so called because he worked behind a lattice (Latin cancellus) at a basilica or law court (see chancel).
In the Roman Empire, a sort of court usher who stood at the latticed railing enclosing the judgment seat to keep the crowd out and admit those entitled to enter. The post gradually gained importance in the Western kingdoms as an intermediary between the petitioners and the judges as a notary or scribe. In England eventually he prepared all important crown documents and became keeper of the great seal and highest judicial officer of the crown. A variant form, canceler, existed in Old English, from Old North French, but was replaced by this central French form.
