c. 1300, ordeinen, "to appoint or admit to the ministry of the Church," also "to decree, enact," from stem of Old French ordener "place in order, arrange, prepare; consecrate, designate" (Modern French ordonner) and directly from Latin ordinare "put in order, arrange, dispose, appoint," from ordo (genitive ordinis) "row, rank, series, arrangement" (see order (n.)). The notion is "to confer holy orders upon." Sense of "establish, set (something) that will continue in a certain order" is from early 14c. Related: Ordained; ordaining.
