cross (n.)

Old English cros "instrument of Christ's crucifixion; symbol of Christianity" (mid-10c.), probably from Old Norse or another Scandinavian source, picked up by the Norse from Old Irish cros, from Latin crux (accusative crucem, genitive crucis) "stake, cross" on which criminals were impaled or hanged (originally a tall, round pole); hence, figuratively, "torture, trouble, misery;" see crux. Also from Latin crux are Italian croce, French croix, Spanish and Portuguese cruz, Dutch kruis, German Kreuz

The modern word is the northern England form and has predominated. Middle English also had two other forms of the same word, arriving from the continent by different paths: cruche, crouche (c. 1200) was from Medieval Latin, with pronunciation as in Italian croce (compare Crouchmas "festival of the Invention of the Cross," late 14c.). Later, especially in southern England, the form crois, croice, from Old French, was the common one (compare croisade, the older form of crusade). The Old English word was rood.

By c. 1200 as "ornamental likeness of the cross, something resembling or in the form of a cross; sign of the cross made with the right hand or with fingers." From mid-14c. as "small cross with a human figure attached; a crucifix;" late 14c. as "outdoor structure or monument in the form of a cross." Also late 14c. as "a cross formed by two lines drawn or cut on a surface; two lines intersecting at right angles; the shape of a cross without regard to religious signification." From late 12c. as a surname.

From c. 1200 in English in the figurative sense "the burden of a Christian; any suffering voluntarily borne for Christ's sake; a trial or affliction; penance in Christ's name," from Matthew x.38, xvi.24, etc. Theological sense "crucifixion and death of Christ as a necessary part of his mission" is from late 14c.

As "a mixing of breeds in the production of animals" from 1760, hence broadly "a mixture of the characteristics of two different things" (1796). In pugilism, 1906, from the motion of the blow, crossing over the opponent's lead (1880s as a verb; cross-counter (n.) is from 1883). As "accidental contact of two wires belonging to different circuits," 1870.

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sea (n.)

Middle English se, seo, from Old English sæ,"sheet of water, sea, lake, pool," from Proto-Germanic *saiwa- (source also of Old Saxon seo, Old Frisian se, Middle Dutch see, Dutch zee, German See, Swedish sjö), of unknown origin, outside connections "wholly doubtful" [Buck], and an IE etymon "has generally been doubted" [Boutkan]. The meaning "any great mass or large quantity" (of anything) is from c. 1200.

Germanic languages also use the more general Indo-European word (represented by English mere (n.1)), but have no firm distinction between "sea" and "lake," either large or small, by inland or open, salt or fresh. This may reflect the Baltic geography where the languages are thought to have originated. The two words are used more or less interchangeably in Germanic, and exist in opposite senses (such as Gothic saiws "lake, marshland," marei "sea;" but Dutch zee "sea," meer "lake"). Compare also Old Norse sær "sea," but Danish , usually "lake" but "sea" in phrases. German See is "sea" (fem.) or "lake" (masc.).

Boutkan writes that the sea words in Germanic likely were originally "lake," and the older word for "sea" is represented by haff. The single Old English word glosses Latin mare, aequor, pontus, pelagus, and marmor. The range in the Old English word included "the expanse of salt water that covers much of the world" to individual great, distinctly limited bodies of water; it also was used of inland seas, bogs, lakes, rivers, and the Bristol Channel.

 Meaning "dark area of the moon's surface" is attested from 1660s (see mare (n.2)); before the invention of telescopes they were supposed to be water. The phrase sea change "transformation," literally "a change wrought by the sea," is attested from 1610, first in Shakespeare ("The Tempest," I.ii). Sea legs, humorous colloquial term implying ability to walk on a ship's deck when she is pitching or rolling is from 1712. At sea in the figurative sense of "perplexed" is attested from 1768, from literal sense (in reference to ships) of "out of sight of land" (c. 1300).

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10th letter of the English alphabet, pronounced "jay," as in "kay" for -k-, but formerly written out as jy, rhyming with -i- and corresponding to French ji.

One of the most stable English letters (it has almost always the same sound), it is a latecomer to the alphabet and originally had no sound value. The letter itself began as a scribal modification of Roman -i- in continental Medieval Latin. The scribes added a "hook" to small -i-, especially in the final position in a word or roman numeral, to distinguish it from the strokes of other letters. The dot on the -i- (and thus the -j-) and the capitalization of the pronoun I are other solutions to the same problems.

In English, -j- was used as a roman numeral throughout Middle English, but the letter -y- was used to spell words ending an "i" sound, so -j- was not needed to represent a sound. Instead, it was introduced into English c. 1600-1640 to take up the consonantal sound that had evolved from the Roman i- since Late Latin times. In Italian, g- was used to represent this, but in other languages j- took the job. This usage is attested earliest in Spanish, where it was in place before 1600.

No word beginning with J is of Old English derivation. [OED]

English dictionaries did not distinguish words beginning in -i- and -j- until 19c., and -j- formerly was skipped when letters were used to express serial order.

In Latin texts printed in modern times, -j- often is used to represent Latin -i- before -a-, -e-, -o-, -u- in the same syllable, which in Latin was sounded as the consonant in Modern English you, yam, etc., but the custom has been controversial among Latinists:

The character J, j, which represents the letter sound in some school-books, is an invention of the seventeenth century, and is not found in MSS., nor in the best texts of the Latin authors. [Lewis]

In English words from Hebrew, -j- represents yodh, which was equivalent to English consonantal y (hence hallelujah) but many of the Hebrew names later were conformed in sound to the modern -j- (compare Jesus).

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eleventh Roman letter, from Greek kappa, from Phoenician kaph or a similar Semitic source, said to mean literally "hollow of the hand" and to be so called for its shape.

Little used in classical Latin, which at an early age conformed most of its words (the exceptions had ritual importance) to a spelling using -c- (a character derived from Greek gamma). In Late Latin, pronunciation of -c- shifted (in the direction of "s"). Greek names brought into Latin also were regularized with a -c- spelling, and then underwent the Late Latin sound-shift; hence the modern pronunciation of Cyrus, Circe. To keep their pronunciation clear, the many Greek words (often Church words) that entered Latin after this shift tended to take Latin -k- for Greek kappa.

K- thus became a supplementary letter to -c- in Medieval Latin, used with Greek and foreign words. But most of the languages descended from Latin had little need of it, having evolved other solutions to the sound shifts.

K- also was scarce in Old English. After the Norman conquest, new scribal habits restricted -c- and expanded the use of -k-, which began to be common in English spelling from 13c. This probably was done because the sound value of -c- was evolving in French and the other letter was available to clearly mark the "k" sound for scribes working in English. For more, see C.

In words transliterated from Arabic, Hebrew, Turkish, Japanese, Hawaiian, etc., it represents several different sounds lumped. In modern use some of them are now with kh-; in older borrowings they often followed traditional English spelling and were written with a C- (Corea, Caaba, etc.).

As a symbol for potassium, it represents Latin kalium "potash." In CMYK as a color system for commercial printing it means "black" but seems to stand for key in a specialized printing sense. Slang meaning "one thousand dollars" is 1970s, from kilo-. K as a measure of capacity (especially in computer memory) meaning "one thousand" also is an abbreviation of kilo-.

As an indication of "strikeout" in baseball score-keeping it dates from 1874 and is said to represent the last letter of struck. The invention of the scorecard symbols is attributed to English-born U.S. newspaperman Henry Chadwick (1824-1908) principally of the old New York "Clipper," who had been writing baseball since 1858, and who explained it thus:

Smith was the first striker, and went out on three strikes, which is recorded by the figure "1" for the first out, and the letter K to indicate how put out, K being the last letter of the word "struck." The letter K is used in this instance as being easier to remember in connection with the word struck than S, the first letter, would be. [Henry Chadwick, "Chadwick's Base Ball Manual," London, 1874]
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