1520s, "a sensation of taste, a flavor distinctive of anything," alteration of reles "scent, taste, aftertaste," (c. 1300), from Old French relais, reles, "something remaining, that which is left behind," from relaisser "to leave behind," from Latin relaxare "loosen, stretch out," from re- "back" (see re-) + laxare "loosen" (from PIE root *sleg- "be slack, be languid").
Especially "a pleasing taste," hence "pleasing quality" in general. The meaning "enjoyment of the taste or flavor of something" is attested from 1640s. The sense of "condiment, that which is used to impart a flavor to plain food to increase the pleasure of eating it" is recorded by 1797, especially a piquant sauce or pickle: The modern stuff you put on hot dogs (or don't) is a sweet green pickle relish.
It forms all or part of: algolagnia; catalectic; laches; languid; languish; lax; lease; lessor; lush; relax; release; relish; slack (adj.); sleep.
It is the hypothetical source of/evidence for its existence is provided by: Greek legein "to leave off, stop," lagnein "to lust;" Latin languere "to be faint, weary," laxus "wide, spacious, roomy;" Old Church Slavonic slabu "lax, weak;" Lithuanian silpnas "weak."
c. 1300, relēsen, "to withdraw, revoke (a decree, etc.), cancel, lift; remit," from Old French relaissier, relesser "to relinquish, quit, let go, leave behind, abandon, acquit," variant of relacher "release, relax," from Latin relaxare "loosen, stretch out" (from re- "back" (see re-) + laxare "loosen," from PIE root *sleg- "be slack, be languid"). Latin relaxare is the source also of Spanish relajar, Italian relassare, and English relax, and the uncle of relish.
Meaning "alleviate, ease" is mid-14c., as is sense of "set free from (duty, etc.); exonerate." From late 14c. as "grant remission, forgive; set free from imprisonment, military service, etc." Also "give up, relinquish, surrender." In law, c. 1400, "to grant a release of property." Of press reports, attested from 1904; of motion pictures from 1912; of music recordings from 1962. As a euphemism for "to dismiss, fire from a job" it is attested in American English since 1904. Related: Released; releasing.
mid-15c., "to season (food), add a sauce or relish to," from sauce (n.). By 1510s in the figurative sense of "intermix or accompany with what gives piquancy or relish." From 1862 as "to speak to impertinently, treat with impertinence." Related: Sauced; saucing.
1846 as a kind of sauce served with meat; 1975 as a kind of dance music; separate borrowings from Spanish, literally "sauce," from Vulgar Latin *salsa "condiment" (see sauce (n.)). In American Spanish it is especially used of a kind of relish with chopped-up ingredients; the music is a "blend" of Latin jazz and rock styles.
mid-15c., "a pickling fluid, seasoning, sauce, something used to give relish to food," from Old French condiment (13c.), from Latin condimentum "spice, seasoning, sauce," from condire "to preserve, pickle, season, put fruit in vinegar, wine, spices, etc.," a variant of condere "put together, store," from assimilated form of com "together" (see con-) + -dere "put," from PIE root *dhe- "to put, place."
Related: Condimental. Middle English also had a verb condite (early 15c.) "to season, prepare or preserve with salt, spices, sugar, etc."
"food," originally especially "Chinese food," 1856, American English (originally in California), from Chinese pidgin English chow-chow (1795) "food; mixed pickle or preserve; mix or medley of any sort," perhaps a reduplication of Chinese cha or tsa "mixed," or Cantonese chaau "to fry, cook." Hence also chow-chow (adj.) "mixed" (1845), since used as a noun in reference to various preserves or relish.
The dog breed of the same name is from 1886, of unknown origin, but some suggest a link to the Chinese tendency to see dogs as edible.
1893, from Swedish smörgåsbord, literally "butter-goose table," from smörgås, "slice of bread and butter," compounded from smör "butter" (see smear (n.)) and gås, literally "goose" (and from the same Germanic root that yielded English goose (n.)).
[Smörgås] properly signifies "a slice of bread-and-butter"; and has come by custom—in much the same way as when we familiarly speak of "taking a sandwich" for partaking of some light refreshment—to be applied synecdochically to the preliminary relish or appetizer partaken of before meals. [Notes and Queries, Nov. 15, 1884]
The final element is bord "table," from Proto-Germanic *burdam "plank, board, table" (see board (n.1)). Figurative sense of "medley, miscellany" is recorded from 1948.