Middle English salten, "prepare with salt, preserve (something) with salt," from Old English sealtan, from Proto-Germanic *salto- (see salt (n.)), and in part from the noun. Related: Salted; salting.
mid-15c., "flavored, spiced," past-participle adjective from season (v.). Meaning "fit for use, matured, hardened" (of timber, etc.), is from 1540s; that of "acclimatized, accustomed" (of persons, animals, etc.) is from 1640s.
Old English sealt "salt, sodium chloride, abundant substance essential to life, used as a condiment and meat preservative," from Proto-Germanic *saltom (source also of Old Saxon, Old Norse, Old Frisian, Gothic salt, Dutch zout, German Salz), from PIE root *sal- "salt."
Applied from early 14c. to various substances resembling common salt. Modern chemistry sense "compound of an acid radical with a base radical" is from 1790; as an ultimate element in alchemy from 1580s. Meaning "experienced sailor" is attested by 1840 (Dana), probably a reference to the salinity of the sea. By 1570s as "that which gives piquancy to discourse or writing or liveliness to a person's character."
Salt long was regarded as having power to repel spiritual and magical evil. Many metaphoric uses reflect that this was once a rare and important resource, such as worth one's salt "efficient, capable" (1830), salt of the earth "persons of worthiness" (Old English, after Matthew v.13). Belief that spilling salt brings bad luck is attested from 16c. To be above (or below) the salt (1590s) refers to customs of seating at a long table according to rank or honor, and placing a large salt-cellar in the middle of the dining table.
Salt-shaker is from 1882. Salt-and-pepper (adj.) "of dark and light color" is by 1915 (pepper-and-salt, 1774, was an old name for a kind of cloth made from dark and light colored wools woven together). To take something with a grain of salt "accept with a certain amount of reserve" is from 1640s, from Modern Latin cum grano salis. The notion is perhaps "modification," hence "allowance, abatement, reserve."
Old English sealt, "salty, briny, containing salt," from Proto-Germanic *saltoz-, from the source of salt (n.). By c. 1300 as "treated with or preserved with salt" (salt fish).
Cold War U.S.-U.S.S.R. nuclear weapons negotiations, 1968, acronym for Strategic Arms Limitation Talks (which would make SALT talks redundant, but the last element sometimes also is understood, especially after their outcome, as treaty).
"the sea; naturally occurring salt water," late Old English sealtera watera. As an adjective from 1520s, "inhabiting salt water or the sea." Salt-water taffy attested by 1886; so called because it originally was sold at seashore resorts, especially Atlantic City, N.J. (see taffy).
"small vessel for holding salt, used on the table," mid-15c., a redundant formation from salt (n.) + saler "salt-cellar" (mid-14c.), from Old French salier "salt box" (Modern French salière) and Medieval Latin salare, from Latin salarium, noun use of adjective meaning "pertaining to salt," from a diminutive of Latin sal "salt" (from PIE root *sal- "salt").
As the etymological connection between saler and "salt" was lost, a redundant salt- was tacked on to the beginning of the word; the second element was influenced by Old French sel "salt" and by unrelated English cellar.