"the language of the (ancient) Romans," Old English latin "Latin, the language of the Romans; any foreign language," from Latin latinium "the Latin language," noun use of the adjective latinius (see Latin (adj.)). The more common form in Old English was læden, from Vulgar Latin *ladinum, which probably was deformed by influence of Old English leoden "language." For "the Latin language" Old English also had lædenspræc.

In Old French the word was used very broadly, "speech, language:" "What Latin was to the learned, that their tongue was to laymen; hence latino was used for any dialect, even Arabic and the language of birds ...." [Donkin, "Etymological Dictionary of the Romance Languages," 1864].

Roughly speaking, Old Latin is the Latin before the classical period including early authors and inscriptions. Classical Latin flourished from about 75 B.C.E. to about 200 C.E., the Latin of Lucretius, Catullus, Caesar, Cicero, Virgil, Horace, Ovid, Livy, Seneca, etc.; it is the standard Latin of the grammars and dictionaries. Late Latin followed the classical period to about 600 and includes the early church fathers. Medieval Latin was the Latin of the Middle Ages, from about 600 to 1500. Modern Latin is Latin as written from about 1500 on, largely by scientific writers in description and classification. Vulgar Latin was the speech of the Roman home and marketplace, going on concurrently under Classical and Late Latin.

This bit of student doggerel said to have been often scrawled on inside covers of school books, seems to date to 1913 in this or similar wording.

Latin's a dead language —

As dead as it can be;

It killed off all the Romans,

And now it's killing me.

"quadruped of the genus Canis," Old English docga, a late, rare word, used in at least one Middle English source in reference specifically to a powerful breed of canine; other early Middle English uses tend to be depreciatory or abusive. Its origin remains one of the great mysteries of English etymology.

The word forced out Old English hund (the general Germanic and Indo-European word, from root from PIE root *kwon-) by 16c. and subsequently was picked up in many continental languages (French dogue (16c.), Danish dogge, German Dogge (16c.). The common Spanish word for "dog," perro, also is a mystery word of unknown origin, perhaps from Iberian. A group of Slavic "dog" words (Old Church Slavonic pisu, Polish pies, Serbo-Croatian pas) likewise is of unknown origin. 

In reference to persons, by c. 1200 in abuse or contempt as "a mean, worthless fellow, currish, sneaking scoundrel." Playfully abusive sense of "rakish man," especially if young, "a sport, a gallant" is from 1610s. Slang meaning "ugly woman" is from 1930s; that of "sexually aggressive man" is from 1950s.  

Many expressions — a dog's life (c. 1600), go to the dogs (1610s), dog-cheap (1520s), etc. — reflect the earlier hard use of the animals as hunting accessories, not pets. In ancient times, "the dog" was the worst throw in dice (attested in Greek, Latin, and Sanskrit, where the word for "the lucky player" was literally "the dog-killer"), which plausibly explains the Greek word for "danger," kindynos, which appears to be "play the dog" (but Beekes is against this).

Notwithstanding, as a dog hath a day, so may I perchance have time to declare it in deeds. [Princess Elizabeth, 1550]

Meaning "something poor or mediocre, a failure" is by 1936 in U.S. slang. From late 14c. as the name for a heavy metal clamp of some kind. Dog's age "a long time" is by 1836. Adjectival phrase dog-eat-dog "ruthlessly competitive" is by 1850s. Phrase put on the dog "get dressed up" (1934) may be from comparison of dog collars to the stiff stand-up shirt collars that in the 1890s were the height of male fashion (and were known as dog-collars from at least 1883).

And Caesar's spirit, ranging for revenge,

With Ate by his side come hot from Hell,

Shall in these confines with a monarch's voice

Cry Havoc! and let slip the dogs of war;

[Shakespeare, "Julius Caesar"]

Middle English short, from Old English sceort, scort "of little length; not tall; of brief duration," probably from Proto-Germanic *skurta- (source also of Old Norse skorta "to be short of," skort "shortness;" Old High German scurz "short"), from PIE root *sker- (1) "to cut," on the notion of "something cut off."

Compare Sanskrit krdhuh "shortened, maimed, small;" Latin curtus "short," cordus "late-born," originally "stunted in growth;" Old Church Slavonic kratuku, Russian korotkij "short;" Lithuanian skursti "to be stunted," skardus "steep;" Old Irish cert "small," Middle Irish corr "stunted, dwarfish," all considered to be from the same root.

Of memories from mid-14c. The sense of "not up to a required standard or amount" is from late 14c.; that of "not far enough to reach the mark" is by 1540s, in archery; that of "having an insufficient quantity" is from 1690s. The meaning "rude, curt, abrupt" is attested from late 14c. The meaning "easily provoked" is from 1590s; perhaps the notion is of being "not long in tolerating."

Of vowels or syllables, "not prolonged in utterance," late Old English. Of alcoholic drinks, colloquially, "unmixed with water, undiluted," by 1839, so called because served in small measure.

Short rib "asternal rib, one of the lower ribs," which are in general shorter than the upper ones, is from c. 1400. Short fuse in the figurative sense of "quick temper" is attested by 1951. Short run "relatively brief period of time" is from 1879. Short story for "work of prose fiction shorter than a novel" is recorded by 1877. To make short work of "dispose of quickly" is attested from 1570s. Phrase short and sweet is from 1530s. To be short by the knees (1733) was to be kneeling; to be short by the head (1540s) was to be beheaded.

late 14c., "statement, belief, or practice handed down from generation to generation," especially "belief or practice based on Mosaic law," from Old French tradicion "transmission, presentation, handing over" (late 13c.) and directly from Latin traditionem (nominative traditio) "a delivering up, surrender, a handing down, a giving up" (also "a teaching, instruction," and "a saying handed down from former times"). This is a noun of action from past-participle stem of tradere "deliver, hand over," from trans- "over" (see trans-) + dare "to give" (from PIE root *do- "to give"). The word is a doublet of treason (q.v.). Meaning "a long-established custom" is from 1590s. The notion is of customs, ways, beliefs, doctrines, etc. "handed down" from one generation to the next.

Tradition is not solely, or even primarily, the maintenance of certain dogmatic beliefs; these beliefs have come to take their living form in the course of the formation of a tradition. What I mean by tradition involves all those habitual actions, habits and customs, from the most significant religious rite to our conventional way of greeting a stranger, which represent the blood kinship of 'the same people living in the same place'. ... We become conscious of these items, or conscious of their importance, usually only after they have begun to fall into desuetude, as we are aware of the leaves of a tree when the autumn wind begins to blow them off—when they have separately ceased to be vital. Energy may be wasted at that point in a frantic endeavour to collect the leaves as they fall and gum them onto the branches: but the sound tree will put forth new leaves, and the dry tree should be put to the axe. [T.S. Eliot, "After Strange Gods"]

Old English dæg "period during which the sun is above the horizon," also "lifetime, definite time of existence," from Proto-Germanic *dages- "day" (source also of Old Saxon, Middle Dutch, Dutch dag, Old Frisian di, dei, Old High German tag, German Tag, Old Norse dagr, Gothic dags), according to Watkins, from PIE root *agh- "a day."  He adds that the Germanic initial d- is "of obscure origin." But Boutkan says it is from PIE root *dhegh- "to burn" (see fever). Not considered to be related to Latin dies (which is from PIE root *dyeu- "to shine").

Meaning originally, in English, "the daylight hours;" it expanded to mean "the 24-hour period" in late Anglo-Saxon times. The day formerly began at sunset, hence Old English Wodnesniht was what we would call "Tuesday night." Names of the weekdays were not regularly capitalized in English until 17c.

From late 12c. as "a time period as distinguished from other time periods." Day-by-day "daily" is from late 14c.; all day "all the time" is from late 14c.  Day off "day away from work" is attested from 1883; day-tripper first recorded 1897. The days in nowadays, etc. is a relic of the Old English and Middle English use of the adverbial genitive.

All in a day's work "something unusual taken as routine" is by 1820. The nostalgic those were the days is attested by 1907. That'll be the day, expressing mild doubt following some boast or claim, is by 1941. To call it a day "stop working" is by 1919; earlier call it a half-day (1838). One of these days "at some day in the near future" is from late 15c. One of those days "a day of misfortune" is by 1936.

open-air game involving kicking a ball, c. 1400; in reference to the inflated ball used in the game, mid-14c. ("Þe heued fro þe body went, Als it were a foteballe," Octavian I manuscript, c. 1350), from foot (n.) + ball (n.1). Forbidden in a Scottish statute of 1424. One of Shakespeare's insults is "you base foot-ball player" [Lear I.iv]. Ball-kicking games date back to the Roman legions, at least, but the sport seems first to have risen to a national obsession in England, c. 1630. Figurative sense of "something idly kicked around, something subject to hard use and many vicissitudes" is by 1530s.

Rules of the game first regularized at Cambridge, 1848; soccer (q.v.) split off in 1863. The U.S. style (known to some in England as "stop-start rugby with padding") evolved gradually 19c.; the first true collegiate game is considered to have been played Nov. 6, 1869, between Princeton and Rutgers, at Rutgers, but the rules there were more like soccer. A rematch at Princeton Nov. 13, with the home team's rules, was true U.S. football. Both were described as foot-ball at Princeton.

Then twenty-five of the best players in college were sent up to Brunswick to combat with the Rutgers boys. Their peculiar way of playing this game proved to Princeton an insurmountable difficulty; .... Two weeks later Rutgers sent down the same twenty-five, and on the Princeton grounds, November 13th, Nassau played her game; the result was joyous, and entirely obliterated the stigma of the previous defeat. ["Typical Forms of '71" by the Princeton University Class of '72, 1869]

"bent or angled piece of metal or other substance used to catch or hold something," Old English hoc "hook, angle," perhaps related to Old English haca "bolt," from Proto-Germanic *hokaz/*hakan (source also of Old Frisian hok, Middle Dutch hoek "a hook;" Dutch haak "a hook, angle, corner, cape," German Haken "hook"), from PIE root *keg- "hook, tooth." For spelling, see hood (n.1).

Also the name of a fireman's tool for tearing into buildings, hence hook-and-ladder (1821). Meaning "holder for a telephone receiver" is from 1885 and continued in use after the mechanism evolved. Boxing sense of "short, swinging blow with the elbow bent" is from 1898. Figurative sense "that which catches, a snare, trap" is from early 15c. Meaning "projecting point of land" is from 1670s; in U.S. use probably reinforced by the Dutch word.

This name is given in New York to several angular points in the North and East rivers; as Corlear's Hook, Sandy Hook, Powles's Hook. [Bartlett, "Dictionary of Americanisms," 1848]

Off the hooks meant "disordered" (16c.), "unhinged" (1610s) and "dead" (1840). By hook or by crook (late 14c.) probably alludes to tools of professional thieves. Hook, line, and sinker "completely" is 1838, a metaphor from angling. Hook-nose (n.) is from 1680s; hook-nosed (adj.) from 1510s. Hook-and-eye as a method of garment fastening is from 1620s.

Hook and eye, a metallic fastening for garments, consisting of a hook, commonly of flattened wire bent to the required shape, and an eye, usually of the same material, into which the hook fits. Under the name of crochet and loop, this form of fastening was in use as early as the fourteenth century. [Century Dictionary]

1660s, scetch, "rough drawing intended to serve as the basis for a finished picture," from Dutch schets or Low German skizze, both apparently being 17c. artists' borrowings from Italian schizzo "sketch, drawing."

This is commonly said to be from Latin *schedius (OED compares schedia "raft," schedium "an extemporaneous poem"), which is from or related to Greek skhedios "temporary, extemporaneous, done or made off-hand," related to skhema "form, shape, appearance" (see scheme (n.)). But according to Barnhart Italian schizzo is a special use of schizzo "a splash, squirt," from schizzare "to splash or squirt," a word of uncertain origin. German Skizze, French esquisse, Spanish esquicio are said to be likewise from Italian schizzo.

The extended sense of "brief account" is from 1660s. The meaning "short and slightly constructed play or performance, usually comic" is from 1789; in music, "short composition of a single movement," 1840. Sketch-book "book with blank leaves of drawing paper" is recorded from 1820; it also was used of printed books composed of literary sketches.

In old slang, a hot sketch (simple sketch for short) was "amusing, ridiculous person" (1909). It turns up first in descriptions of stage entertainment, and a theatrical help-wanted ad from 1906 seeks "a good hot sketch team" for "all circus and vaudeville lines."

Miss Cora Martini, the Cuban dancer, might be termed a hot sketch. When Girard announced her, the crowd asked her age. Girard said he didn't know as he never liked to ask ladies personal questions. The house told him it was just as well, seeing she wouldn't tell him anyhow. ["Amateur Night at the Gotham," Brooklyn Weekly Chat, Nov. 30, 1907]

Old English læfan "to allow to remain in the same state or condition; to let remain, allow to survive; to have left (of a deceased person, in reference to heirs, etc.); to bequeath (a heritage)," from Proto-Germanic *laibjanan (source also of Old Frisian leva "to leave," Old Saxon farlebid "left over"), causative of *liban "remain" (source of Old English belifan, German bleiben, Gothic bileiban "to remain"), from PIE root *leip- "to stick, adhere."

The Germanic root seems to have had only the sense "remain, continue" (which was in Old English as well but has since become obsolete), which also is in Greek lipares "persevering, importunate." But this usually is regarded as a development from the primary PIE sense of "adhere, be sticky" (compare Lithuanian lipti, Old Church Slavonic lipet "to adhere," Greek lipos "grease," Sanskrit rip-/lip- "to smear, adhere to."

Originally a strong verb (past participle lifen), it early switched to a weak form. Meaning "go away, take one's departure, depart from; leave behind" (c. 1200) comes from notion of "leave behind" (as in to leave the earth "to die;" to leave the field "retreat"). From c. 1200 as "to stop, cease; give up, relinquish, abstain from having to do with; discontinue, come to an end;" also "to omit, neglect; to abandon, forsake, desert; divorce;" also "allow (someone) to go."

Colloquial use for "let, allow" is by 1840, said by OED to be chiefly American English. Not related to leave (n.). To leave out "omit" is from late 15c. To leave (something) alone is from c. 1400; to leave (something) be is from 1825. To leave (something/nothing) to be desired is from 1780. To leave it at that is from 1902. Leave off is from c. 1400 as "cease, desist" (transitive); early 15c. as "stop, make an end" (intransitive).