late 14c., cerymonye, "a religious observance, a solemn rite," from Old French ceremonie and directly from Medieval Latin ceremonia, from Latin caerimonia "holiness, sacredness; awe; reverent rite, sacred ceremony," an obscure word, possibly of Etruscan origin, or a reference to the ancient rites performed by the Etruscan pontiffs at Caere, near Rome.

Introduced in English by Wyclif. Also from late 14c. as "a conventional usage of politeness, formality." Disparaging sense of "mere formality" is by 1550s.

1550s, "relating to outward forms or rites," also, of persons, "punctilious in matters of formality," from French cérémonieux or directly from Late Latin caerimoniosus, from Latin caerimonia "reverent rite, sacred ceremony" (see ceremony). Meaning "full of show and ceremony" is from 1610s. Related: Ceremoniously; ceremoniousness.

c. 1400, "belonging to (religious) ritual," also as a noun, "a ceremonial practice," from Late Latin caerimonialis "pertaining to ceremony," from caerimonia (see ceremony). Related: Ceremonially.

Ceremonial means connected with or constituting or consisting of or fit for a ceremony (i.e. a piece of ritual or formality) or ceremonies .... Ceremonious means full of or resulting from ceremony i.e. attention to forms .... [Fowler]

"act or ceremony of baptizing," c. 1300, verbal noun from christen (v.). Old English had cristnung.

1941, literally "daughter of command;" a Jewish girl who has reached age 12, the age of religious majority. Extended to the ceremony held on occasion of this.