cashew (n.)
in early use also cachou, etc., 1703, a shortening of French acajou, from older Portuguese acajú from Tupi (Brazil) acajuba, name of the tree that produces the nut.
cashier (n.)
"person in charge of money," 1590s, from Middle French caissier "treasurer," from caisse "money box" (see cash (n.)). The immediate source of the English word might be Middle Dutch kassier.
cashier (v.)
"dismiss," 1590s, from Middle Dutch casseren, kaseeren "to cast off, discharge," from French casser "to discharge, annul," from Late Latin cassare "annul," from Latin cassus "void, empty" (see caste (n.)). Related: Cashiered; cashiering.
cashmere (n.)
1680s, "shawl made of cashmere wool," from the old spelling of Kashmir, Himalayan kingdom where wool was obtained from long-haired goats. As a name for this kind of woolen fabric, favored for shawls, etc., it is attested from 1822.
Casimir
masc. proper name, from Medieval Latin Casimirus from Polish Kazimierz, literally "proclaimer of peace," from kazać "to preach" + mir "peace" (see Mir).
casing (n.)
1570s, "action of fitting with a case," verbal noun from case (v.). Meaning "a covering" is from 1839.
casino (n.)
1744, "public room for music or dancing," from Italian casino, literally "a little house," diminutive of casa "house," from Latin casa "hut, cottage, cabin," which is of uncertain origin. The card game (also cassino) is attested by that name from 1792. Specifically as "building for aristocratic gambling" by 1820, first in an Italian context.
[T]he term Casino [is] indiscriminately applied to a set of farm offices, a country-seat, a gambling house, and a game of cards ... [Jane Waldie Watts, "Sketches Descriptive of Italy in the Years 1816 and 1817," London 1820]
cask (n.)
mid-15c., from Middle French casque "cask; helmet," from Spanish casco "skull, cask, helmet," originally "potsherd," from cascar "to break up," from Vulgar Latin *quassicare, frequentative of Latin quassare "to shake, shatter" (see quash). The sense evolution is unclear.
casket (n.)
mid-15c., "small box for jewels, etc.," possibly a diminutive of English cask with -et, or from a corruption of Middle French casset (see cassette). Meaning "coffin" is American English, probably euphemistic, attested by 1832.
Caskets! a vile modern phrase, which compels a person ... to shrink ... from the idea of being buried at all. [Hawthorne, "Our Old Home," 1863]
Caspian
inland sea of central Asia, 1580s, from Latin Caspius, from Greek Kaspios, named for native people who lived on its shores (but who were said to be originally from the Caucasus), Latin Caspii, from a native self-designation, perhaps literally "white."
casque (n.)
"armor for the head," 1570s, from French casque (see cask).
Cassandra
fem. proper name, from Greek Kasandra, Kassandra, daughter of Priam of Troy, seduced by Apollo who gave her the gift of prophecy, but when she betrayed him he amended it so that, though she spoke truth, none would believe her. Used figuratively since 1660s.

The name is of uncertain origin, though the second element looks like a fem. form of Greek andros "of man, male human being." Watkins suggests PIE *(s)kand- "to shine" as source of second element, hence possibly "praise of men."
cassation (n.)
"anullment," early 15c., from Old French cassation, from casser, from Late Latin cassare, from Latin quassare (see quash).
cassava (n.)
1560s, from French cassave, Spanish casabe, or Portuguese cassave, from Taino (Arawakan) caçabi. Earlier in English as cazabbi (1550s).
casserole (n.)
1706, "stew pan," from French casserole "sauce pan" (16c.), diminutive of Middle French casse "pan" (14c.), from Provençal cassa "melting pan," from Medieval Latin cattia "pan, vessel," possibly from Greek kyathion, diminutive of kyathos "cup for the wine bowl." Originally the pan, since c. 1930 also of the dishes cooked in it, via cookery phrases such as en casserole, à la casserole.
cassette (n.)
1793, "little box," from French cassette, from Middle French casset, diminutive of Old North French casse "box" (see case (n.2)). Meaning "magnetic tape recorder cartridge" is from 1960.
cassia (n.)
cinnamon-like plant, late Old English, from Latin cassia, from Greek kasia, from Hebrew q'tsi-ah "cassia," from qatsa "to cut off, strip off bark."
Cassiopeia (n.)
northern constellation, in Greek mythology queen of Ethiopia and mother of Andromeda, from Latinized form of Greek Kassiepeia, Kassiopeia, of unknown etymology. Related: Cassiopeian.
cassis (n.)
black currant liquor, 1907, from French cassis (16c.) "black currant," apparently from Latin cassia (see cassia). The modern liqueur dates from mid-19c.
Cassius
Roman gens, one of the oldest families of Rome. The conspirator against Caesar was C. Cassius Longinus.
cassock (n.)
1540s, "long loose gown," from Middle French casaque "long coat" (16c.), probably ultimately from Turkish quzzak "nomad, adventurer," (the source of Cossack), from their typical riding coat. Or perhaps from Arabic kazagand, from Persian kazhagand "padded coat," from kazh "raw silk" + agand "stuffed." Chiefly a soldier's cloak 16c.-17c.; ecclesiastical use is from 1660s.
cassowary (n.)
1610s, via French or Dutch, from Malay (Austronesian) kasuari.
cast (v.)
c. 1200, "to throw, fling, hurl," from a Scandinavian source akin to Old Norse kasta "to throw" (cognate with Swedish kasta, Danish kaste, North Frisian kastin), of uncertain origin. Meaning "to form in a mold" is late 15c. In the sense of "to throw" it replaced Old English weorpan (see warp (v.)), and itself largely has been superseded now by throw, though cast still is used of fishing lines and glances. Meaning "calculate, find by reckoning; chart (a course)" is from c. 1300.
cast (n.)
mid-13c., "a throw, an act of throwing," from cast (v.). In early use especially of dice, hence figurative uses relating to fortune or fate. Meaning "that which is cast" is from c. 1550s. Meaning "dash or shade of color" is from c. 1600. The sense of "a throw" carried an idea of "the form the thing takes after it has been thrown," which led to widespread and varied meanings, such as "group of actors in a play" (1630s). OED finds 42 distinct noun meaning and 83 verbal ones, with many sub-definitions. Many of the figurative senses converged in a general meaning "sort, kind, style" (mid-17c.). A cast in the eye (early 14c.) preserves the older verbal sense of "warp, turn."
cast iron (n.)
1660s, from cast "made by melting and being left to harden in a mold" (1530s), past participle adjective from cast (v.) in its sense "to throw something (in a particular way)," c. 1300, especially "form metal into a shape by pouring it molten" (1510s). From 1690s as an adjective, cast-iron.
cast-off (n.)
1741, from verbal phrase (c. 1400), from cast (v.) + off (adv.). From 1746 as a past participle adjective.
castanet (n.)
usually castanets, 1640s, from French castagnette or directly from Spanish castañeta diminutive of castaña "chestnut," from Latin castanea (see chestnut).
castaway (n.)
late 15c., "one who is rejected," from the verbal phrase (c. 1300, literal and figurative), from cast (v.) + away (adv.). Specific sense "one adrift at sea" is from 1799. The adjective is first recorded 1540s.
caste (n.)
1550s, "a race of men," from Latin castus "chaste," from castus "cut off, separated; pure" (via notion of "cut off" from faults), past participle of carere "to be cut off from" (and related to castration), from PIE *kas-to-, from root *kes- "to cut" (source also of Latin cassus "empty, void"). Originally spelled cast in English and later often merged with cast (n.) in its secondary sense "sort, kind, style."

Application to Hindu social groups was picked up by English in India 1610s from Portuguese casta "breed, race, caste," earlier casta raça, "unmixed race," from the same Latin word. The current spelling of of the English word is from this reborrowing. Caste system is first recorded 1840.
castellan (n.)
late 14c., from Old North French castelain (Modern French châtelaine; see chatelaine).
castellated (adj.)
"furnished with turrets and battlements," 1670s, from Medieval Latin castellatus "built like a castle," past participle of castellare "to fortify as a castle," from Latin castellum "fort" (see castle (n.)). Related: Castellation.
caster (n.1)
also sometimes castor, "person or thing that casts," late 14c., agent noun from cast (v.). Meaning "pepper shaker, small perforated container" is from 1670s, on notion of "throwing."
caster (n.2)
"wheel and swivel attached to furniture," 1748, agent noun from cast (v.) in the old sense of "turn." Also sometimes castor.
castigate (v.)
c. 1600, from Latin castigatus, past participle of castigare "to correct, set right; purify; chastise, punish," from castus "pure" (see caste) + agere "to do" (from PIE root *ag- "to drive, draw out or forth, move"). The notion behind the word is "make someone pure by correction or reproof."
If thou didst put this soure cold habit on To castigate thy pride, 'twere well. [Shakespeare, "Timon" IV.iii (1607)]
Related: Castigated; castigating; castigator; castigatory.
castigation (n.)
late 14c., castigacioun, from Latin castigationem (nominative castigatio) "a correcting, reproof, chastizing," noun of action from past participle stem of castigare "to correct, set right; purify" (see castigate).
Castile
medieval Spanish county and later kingdom, from Vulgar Latin castilla, from Latin castella, plural of castellum "castle, fort, citadel, stronghold" (see castle (n.)); so called in reference to the many fortified places there during the Moorish wars. The name in Spanish is said to date back to c.800. Related: Castilian. As a fine kind of soap, in English from 1610s.
casting (n.)
c. 1300, "a throwing; late 14c., "a metal casting, a product of a cast;" verbal noun from cast (v.). Theatrical sense is from 1814. Casting couch in the naughty-Hollywood sense is from 1948.
castle (n.)
late Old English castel "village" (this sense from a biblical usage in Vulgar Latin); later "large fortified building, stronghold," in this sense from Old North French castel (Old French chastel, 12c.; Modern French château), from Latin castellum "a castle, fort, citadel, stronghold; fortified village," diminutive of castrum "fort," from Proto-Italic *kastro- "part, share;" cognate with Old Irish cather, Welsh caer "town" (and perhaps related to castrare via notion of "cut off;" see caste). In early bibles, castle was used to translate Greek kome "village."

This word also had come to Old English as ceaster and formed the -caster and -chester in place names. Spanish alcazar "castle" is from Arabic al-qasr, from Latin castrum. Castles in Spain translates 14c. French chastel en Espaigne (the imaginary castles sometimes stood in Brie, Asia, or Albania) and probably reflects the hopes of landless knights to establish themselves abroad. The statement that an (English) man's home is his castle is from 16c.
castle (v.)
move in chess, recorded under this name from 1650s, from castle (n.), as an old alternative name for the rook, one of the pieces moved. Related: Castled; castling.
castor (n.)
late 14c., "beaver," from Old French castor (13c.), from Latin castor "beaver," from Greek kastor "beaver," literally "he who excels," also the name of one of the divine twins (with Pollux), worshipped by women in ancient Greece as a healer and preserver from disease.

His name was given to secretions of the animal (Latin castoreum), which were used medicinally in ancient times. (Through this association his name replaced the native Latin word for "beaver," which was fiber.) In English, castor is attested in this sense from c. 1600. Modern castor oil is first recorded 1746; it is made from seeds of the plant Ricinus communis but supposedly possesses the laxative qualities (and taste) of beaver juice.
castrate (v.)
1610s (implied in castrated), back-formation from castration (q.v.), or from Latin castratus, past participle of castrare. The figurative sense is attested earlier (1550s). Related: Castrating.
castrati (n.)
plural of castrato.
castration (n.)
early 15c., castracioun, from Latin castrationem (nominative castratio), noun of action from past participle stem of castrare "to castrate, emasculate," supposedly from a noun *castrum "knife, instrument that cuts," from PIE root *kes- "to cut" (see caste). Freud's castration complex is attested from 1914 in English (translating German Kastrationsangst).
castrato (n.)
1763, from Italian castrato, from Latin castratus (see castration).
casual (adj.)
late 14c., "subject to or produced by chance," from Middle French casuel (15c.), from Late Latin casualis "by chance," from Latin casus "chance, occasion, opportunity; accident, event" (see case (n.1)).

Of persons, in the sense of "not to be depended on, unmethodical," it is attested from 1883; meaning "showing lack of interest" is from 1916. Of clothes, "informal," from 1939. Related: Casually.
casualness (n.)
1730, from casual (adj.) + -ness.
casualty (n.)
early 15c., "chance, accident; incidental charge," from casual (adj.) on model of royalty, penalty, etc. Casuality had some currency 16c.-17c. but is now obsolete. Meaning "losses in numbers from a military or other troop" is from late 15c. Meaning "an individual killed, wounded, or lost in battle" is from 1844.
casuist (n.)
c. 1600, "one who studies and resolves cases of conscience," from French casuiste (17c.) or Spanish casuista (the French word also might be from Spanish), Italian casista, all from Latin casus (see case (n.1)) in its Medieval Latin sense "case of conscience." Often since 17c. in a sinister or contemptuous sense. Related: Casuistic; casuistical; casuistically; casuistry.
Casuistry ... destroys, by distinctions and exceptions, all morality, and effaces the essential difference between right and wrong. [Bolingbroke, 1736]
casus belli (n.)
an act justifying war, 1849, from Latin casus "case" (see case (n.1)) + belli, genitive of bellum "war" (see bellicose).
CAT
1975, medical acronym for computerized axial tomography or something like it. Related: CAT scan.