>Кстати глагол ordain (1. посвящать в духовный сан 2.
>предопределять; предписывать; уготавливать) - не от слова ли
>"орда"?

ordain
c.1290, "to appoint or admit to the ministry of the Church," from stem of O.Fr. ordener, from L. ordinare "put in order, arrange, dispose, appoint," from ordo (gen. ordinis) "order." The notion is "to confer holy orders upon" (see order). Meaning "to decree, enact" is from 1297; sense of "to set (something) that will continue in a certain order" is from c.1315.
order (n.)
c.1225, "body of persons living under a religious discipline," from O.Fr. ordre (11c.), from earlier ordene, from L. ordinem (nom. ordo) "row, rank, series, arrangement," originally "a row of threads in a loom," from Italic root *ored(h)- "to arrange, arrangement" (cf. ordiri "to begin to weave," e.g. in primordial), of unknown origin. Meaning "a rank in the (secular) community" is first recorded c.1300; meaning "command, directive" is first recorded 1548, from the notion of "to keep in order." Military and honorary orders grew our of the fraternities of Crusader knights. Business and commerce sense is attested from 1837. In natural history, as a classification of living things, it is first recorded 1760. Meaning "condition of a community which is under the rule of law" is from 1483. Phrase in order to (1655) preserves etymological notion of "sequence." The word reflects a very medieval notion: "a system of parts subject to certain uniform, established ranks or proportions," and was used of everything from architecture to angels. The verb is c.1240, from the noun. In short order "without delay" is from 1834, Amer.Eng.; order of battle is from 1769.
orderly (adv.)
1477, "in due order," from order (q.v.). As a noun meaning "military attendant who carries orders" it is first attested 1781 (short for orderly corporal, etc.). Extended 1809 to an attendant at a hospital (originally a military hospital) charged with keeping things in order and clean.
ordinal (n.)
1387, "book setting forth the order of services in the Church," from L.L. adj. ordinalis "showing order, denoting an order of succession," from L. ordo (gen. ordinis) "row, series" (see order). The adj. in Eng., "marking position in an order or series," is attested from 1599.
ordinance
1303, "an authoritative direction, decree, or command" (narrower or more transitory than a law), from O.Fr. ordenance, from M.L. ordinantia, from L. ordinantem (nom. ordinans), prp. of ordinare "put in order" (see ordain). By c.1330 senses had emerged of "arrangement in ranks or rows" (especially in order of battle), also "warlike provisions, equipment" (a sense now in ordnance, q.v.).
ordinary (adj.)
c.1460, "belonging to the usual order or course," from O.Fr. ordinarie, from L. ordinarius "customary, regular, usual, orderly," from ordo (gen. ordinis) "order" (see order). Various noun usages, dating to c.1380 and common until 19c., now largely extinct except in out of the ordinary (1893). In British education, Ordinary level "lowest of the three levels of General Certificate of Education" is attested from 1947 (abbrev. O level).
ordination
1432, "the act of conferring holy orders," from M.Fr. ordinacion (12c.), from L. ordinationem (nom. ordinatio) "a setting in order, ordinance," from ordinatus, pp. of ordinare "arrange" (see ordain).
ordnance
"cannon, artillery," a clipped form of ordinance (q.v.) which was attested from 1390 in the sense of "military materials, provisions of war;" a sense now obsolete but which led to those of "engines for discharging missiles" (c.1430) and "branch of the military concerned with stores and materials" (1485). The shorter word was established in these distinct senses by 17c. Ordnance survey (1833), official survey of Great Britain and Ireland, was undertaken by the government under the direction of the Master-General of the Ordnance (a natural choice, because gunners have to be skilled at surveying ranges and distances).