mid-12c., pes, "freedom from civil disorder, internal peace of a nation," from Anglo-French pes, Old French pais "peace, reconciliation, silence, permission" (11c., Modern French paix), from Latin pacem (nominative pax) "compact, agreement, treaty of peace, tranquility, absence of war" (source of Provençal patz, Spanish paz, Italian pace), from PIE root *pag- "to fasten" (which is the source also of Latin pacisci "to covenant or agree;" see pact), on the notion of "a binding together" by treaty or agreement.

It replaced Old English frið, also sibb, which also meant "happiness." The modern spelling is from 1500s, reflecting vowel shift. From mid-13c. as "friendly relations between people." The sense of "spiritual peace of the heart, soul or conscience, freedom from disturbance by the passions" (as in peace of mind) is from c. 1200. Sense of "state of quiet or tranquility" is by 1300, as in the meaning "absence or cessation of war or hostility." Specifically as "treaty or agreement made between conflicting parties to refrain from further hostilities," c. 1400.

Used in various greetings from c. 1300, from Biblical Latin pax, Greek eirēnē, which were used by translators to render Hebrew shalom, properly "safety, welfare, prosperity." As a type of hybrid tea rose (developed 1939 in France by François Meilland), so called from 1944.

The Native American peace pipe, supposedly smoked as the accompaniment of a treaty, is recorded by 1760. Peace-officer "civil officer whose duty it is to preserve public peace" is attested from 1714. Peace offering "offering that procures peace or reconciliation, satisfaction offered to an offended person" is from 1530s. Phrase peace with honor dates to 1607 (in "Coriolanus"). The U.S. Peace Corps was set up March 1, 1962. Peace sign, in reference to both the hand gesture and the graphic, is attested from 1968.

1540s, "make compensation for, spend, pay for" (a sense now archaic); 1570s, "satisfy by payment," from Old French defraier, defrayer (15c.), perhaps from de- "out" (see de-) + fraier "spend," from frais "costs, damages caused by breakage," from Latin fractum, neuter past participle of frangere "to break" (from PIE root *bhreg- "to break").

Alternative etymology traces second element to Old High German fridu "peace," via Vulgar Latin *fredum "fine, cost." Compare affray. For possible sense development, compare pay from pax "peace."

also over-pay, "to pay in excess, pay more than is necessary," c. 1600, from over- + pay (v.). Related: Overpaid; overpaying; overpayment.

also *pak-, Proto-Indo-European root meaning "to fasten."

It forms all or part of: Areopagus; appease; appeasement; compact (adj.) "concentrated;" compact (n.1) "agreement;" fang; impact; impale; impinge; newfangled; pace (prep.) "with the leave of;" pacific; pacify; pact; pagan; page (n.1) "sheet of paper;" pageant; pale (n.) "limit, boundary, restriction;" palette; palisade; patio; pawl; pax; pay; peace; peasant; pectin; peel (n.2) "shovel-shaped instrument;" pole (n.1) "stake;" propagate; propagation; travail; travel.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit pasa- "cord, rope," pajra- "solid, firm;" Avestan pas- "to fetter;" Greek pegnynai "to fix, make firm, fast or solid," pagos "pinnacle, cliff, rocky hill;" Latin pangere "to fix, to fasten," pagina "column," pagus "district;" Slavonic paž "wooden partition;" Old English fegan "to join," fon "to catch seize."

late 14c., paiable, "to be paid, that can be or is to be paid," from pay (v.) + -able or from Old French paiable. From late 13c. as a surname, from the Old French word in its other sense, "of good quality." Related: Payability.

also pay-back, 1946, "net return on profits from an investment," from the verbal phrase, from pay (v.) + back (adj.). Meaning "revenge, retaliation" is by 1957.

"person to whom money is paid," 1758, from pay (v.) + -ee.

late 14c., "person who pays," originally wages, later taxes (early 15c.), from Old French paiere (13c.), agent noun from paier (see pay (v.)).

also pay-load, by 1914, from pay + load (n.). Originally the part of a truck's (later an aircraft's) load from which revenue is derived (passengers, cargo, mail); figurative sense of "bombs, etc. carried by a plane or missile" is from 1936.

late 14c., paiement, "action of paying, repayment of a debt; amount due as a payment," from Old French paiement (13c.), from paiier (see pay (v.)). Meaning "thing or sum of money given in discharge of a debt" is from mid-15c.