Roman fem. given name, fem. of Quintillus, diminutive of quintus "fifth" (related to quinque "five;" from PIE root *penkwe- "five"). The Quintillians were a Montanist sect, said to have been named for their prophetess Quintilla.
"one who conducts a religious service, one who administers a sacrament," 1836, from noun use of Medieval Latin officiantem (nominative officians) "performing religious services," present participle of officiare "to perform religious services," from Latin officium "a service; an official duty; ceremonial observance" (in Medieval Latin, "church service"); see office.
1844, American English, from the name of Jacob Amman, 17c. Swiss Mennonite preacher who founded the sect. The surname is a contraction of Old High German ambahtman, title of an official in the German Swiss cantons, from ambet "office" (German Amt; see amt, a Celtic borrowing related to the beginning of ambassador) + man "man." Originally also spelled Omish, which reflects the pronunciation in Pennsylvania German dialect. As a noun, by 1884. Other early names for the sect were Ammanite and, in a European context, Upland Mennonite.
popular name of a German-American Anabaptist sect, 1756, from (Pennsylvania) German Tunker, from tunken, dunken "to dip, soak" (see dunk (v.)). So called because they practice adult baptism by triple immersion. The proper name is Brethren.