1560s, "a law or decree," from Latin sanctionem (nominative sanctio) "act of decreeing or ordaining," also "a decree, an ordinance, a law," noun of action from past-participle stem of sancire "to decree, confirm, ratify, make sacred" (see saint (n.)).

Originally especially of ecclesiastical decrees. The extended sense of "express authoritative permission" is by 1720, hence the looser sense of "the conferring of authority upon (an opinion, practice or sentiment); confirmation of support derived from public approval" (1738). Moral sanction, in Bentham's philosophy, is "the knowledge of how one's neighbors will take a given act, as a motive for doing or not doing it" [Century Dictionary].

As "a penalty enacted according to a provision in a law to enforce obedience to it" from 1630s; in later 17c. also "a provision of a law which enforces obedience through rewards or penalties." Hence the modern sense of "economic or quasi-military action by a state against another," usually to enforce terms of a law or treaty that has been violated (1919).

1778, "confirm by sanction, make valid or binding;" by 1797 as "to permit authoritatively," also in a general sense, "give countenance or support to, approve;" from sanction (n.). Seemingly contradictory meaning "impose a penalty on" is from 1956 but is rooted in an old legalistic sense of the noun. Related: Sanctioned; sanctioning.

in international diplomacy, by 1900, plural of sanction (n.) in the sense of "part or clause of a law which spells out the penalty for breaking it" (1650s).

"superlatively sacred or inviolable," c. 1600, from Latin sacrosanctus "inviolable, protected by religious sanction, consecrated with religious ceremonies," from sacro, ablative of sacrum "religious sanction, religious rite" (from neuter singular of sacer "sacred") + sanctus, past participle of sancire "make sacred" (for both, see sacred). Earlier in partially Englished form sacro-seint (c. 1500).

late 14c., "hallowed, consecrated, or made holy by association with divinity or divine things or by religious ceremony or sanction," past-participle adjective from a now-obsolete verb sacren "to make holy" (c. 1200), from Old French sacrer "consecrate, anoint, dedicate" (12c.) or directly from Latin sacrare "to make sacred, consecrate; hold sacred; immortalize; set apart, dedicate," from sacer (genitive sacri) "sacred, dedicated, holy, accursed." OED writes that, in sacred, "the original ppl. notion (as pronunciation indicates) disappeared from the use of the word, which is now nearly synonymous with L. sacer."

This is from Old Latin saceres, from PIE root *sak- "to sanctify." Buck groups it with Oscan sakrim, Umbrian sacra and calls it "a distinctive Italic group, without any clear outside connections." De Vaan has it from a PIE root *shnk- "to make sacred, sanctify," and finds cognates in Hittite šaklai "custom, rites," zankila "to fine, punish." Related: Sacredness. The Latin nasalized form is sancire "make sacred, confirm, ratify, ordain" (as in saint, sanction). An Old English word for "sacred" was godcund.

The meaning "of or pertaining to religion or divine things" (opposed to secular or profane) is by c. 1600. The transferred sense of "entitled to respect or reverence" is from 1550s. Sacred cow as an object of Hindu veneration is by 1793; its figurative sense of "one who or that which must not be criticized" is in use by 1910 in U.S. journalism, reflecting Western views of Hinduism. Sacred Heart "the heart of Jesus as an object of religious veneration" is by 1823, short for Sacred Heart of Jesus or Mary.

late 14c., "praise" (a sense now obsolete), from Old French aloance "sanction, granting, allocation," from aloer "allot, apportion, assign" (see allow). As with allow, the English word involves senses of two different French words.

The meaning "sanction, approval, tolerance" is from 1550s. The sense of "a sum allotted to meet expenses" is from c. 1400. In accounts, the meaning "a sum placed to one's credit" is attested from 1520s. The mechanical meaning "permissible deviation from a standard" is from 1903. To make allowances is to add or deduct a sum from someone's account for some special circumstance; figurative use of the phrase is attested from 1670s.

"leave, sanction; the act of allowing," early 15c., permissioun, from Old French permission and directly from Latin permissionem (nominative permissio) "a giving up, a yielding; permission," noun of action from past-participle stem of permittere (see permit (v.)).

late 14c., "to refuse to praise" (a sense now obsolete), from Old French desalouer "to blame," from des- "not, opposite of" (see dis-) + alouer (see allow). Meanings "to reject, refuse to receive or acknowledge," also "refuse to allow, refuse to approve or sanction" are from c. 1400. Related: Disallowed; disallowing; disallowance.

c. 1600, "dictatorial" (a sense now restricted to authoritarian), earlier auctoritative (implied in auctoritativeli "with official approval or sanction"), from Medieval Latin auctoritativus, from Latin auctoritatem (see authority).

The meaning "having due authority, entitled to credence or obedience" is from 1650s; that of "proceeding from proper authority" is from 1809. Related: Authoritatively; authoritativeness.

"act by which a competent authority gives sanction and validity to something done by another," mid-15c., ratificacion, from Old French ratification (14c.) and directly from Medieval Latin ratificationem (nominative ratificatio), noun of action from past-participle stem of ratificare "to confirm, approve" (see ratify).