Online Etymology Dictionary

host (n.2): "a multitude," especially an army organized for war, mid-13c., from Old French ost, host "army" (10c.), from Medieval Latin hostis "army, war-like expedition," from Latin hostis "enemy, foreigner, stranger," from the same root as host (n.1). Replaced Old English here (see harry (v.)), and in turn has been largely superseded by army. The generalized meaning of "large number" is first attested 1610s. The Latin h- was lost in Old French, then restored in Old French and Middle English spelling, and in modern English also in pronunciation. Lord of Hosts translates Hebrew Jehovah Ts'baoth (which appears more than 260 times throughout the Bible) and seems to refer to both heavenly (angelic) and earthly hosts.
host (n.3): "body of Christ, consecrated bread," c. 1300, from Latin hostia "sacrifice," also "the animal sacrificed, victim," probably ultimately related to host (n.1) in its root sense of "stranger, enemy." Applied in Church Latin to Christ, in Medieval Latin to the consecrated bread.
host (v.): "to serve as a host," early 15c., originally in the sense "give entertainment, receive as a guest," from host (n.1). Related: Hosted; hosting.
hosta (n.): 1828, plant genus of the lily family, coined 1812 in Modern Latin from name of Austrian physician and botanist Nicolaus Thomas Host (1761-1834).
hostage (n.): late 13c., from Old French ostage, hostage "kindness, hospitality; residence, dwelling; rent, tribute; compensation; guarantee, pledge, bail; person given as security or hostage" (11c., Modern French ôtage), which is of uncertain origin. Either from hoste "guest" (see host (n.1)) via notion of "a lodger held by a landlord as security" [Watkins, Barnhart]; or else from Late Latin obsidanus "condition of being held as security," from obses "hostage," from ob- "before" + base of sedere "to sit," with spelling influenced by Latin hostis. [OED, Century Dictionary]. Modern political/terrorism sense is from 1970.
hostel (n.): early 13c., "inn, house of entertainment," from Old French ostel, hostel "house, home, dwelling; inn, lodgings, shelter" (11c., Modern French hôtel), from Medieval Latin hospitale "inn; large house" (see hospital). Obsolete after 16c., revived 1808, along with hostelry by Sir Walter Scott. Youth hostel is recorded by 1931.
hostelry (n.): late 14c. (as a surname from early 14c.), from Old French ostelerie, hostelerie "house, guest-house; kitchen; hospice, almshouse" (12c., Modern French hôtellerie), from hostel "house, home" (see hostel). Rare in modern English before Scott. Alternative hostry (from Old French hosterie, from hoste) was in use late 14c. through 18c. Tindale, in Luke ii, has "There was no roome for them with in, in the hostrey" [1526].
hostess (n.): late 13c., "woman who keeps an inn or public hotel," from host (n.1) + -ess, or from Old French ostesse, hostesse "hostess; servant; guest" (Modern French hôtesse). Old French also had ostelaine; the Latin word was hospita. Meaning "woman who presides at a dinner party, etc." recorded by 1822. Also used mid-20c. in sense "female who entertains customers in nightclubs," with overtones of prostitution.
hostile (adj.): late 15c., from Middle French hostile "of or belonging to an enemy" (15c.) or directly from Latin hostilis "of an enemy, belonging to or characteristic of the enemy; inimical," from hostis "enemy" (see guest (n.)). The noun meaning "hostile person" is recorded from 1838, American English, a word from the Indian wars. Related: Hostilely.
hostility (n.): early 15c., "hostile action," from Middle French hostilité "enmity" (15c.), or directly from Late Latin hostilitatem (nominative hostilitas) "enmity," from Latin hostilis "inimical," from hostis "enemy" (see guest (n.)). Hostilities in the sense of "warfare" attested from 1610s.
hostler (n.): formerly also hosteler, late 14c., "one who tends to horses at an inn," also, occasionally, "innkeeper," from Anglo-French hostiler, Old French ostelier, hostelier "innkeeper; steward in a monastery" (12c., Modern French hôtelier), from Medieval Latin hostilarius "the monk who entertains guests at a monastery," from hospitale "inn" (see hospital). Compare ostler.
hot (adj.): Old English hat "hot, flaming, opposite of cold," used of the sun or air, of fire, of objects made hot; also "fervent, fierce, intense, excited," from Proto-Germanic *haita- (source also of Old Saxon and Old Frisian het, Old Norse heitr, Middle Dutch and Dutch heet, German heiß "hot," Gothic heito "heat of a fever"), from PIE root *kai- "heat" (source also of Lithuanian kaistu "to grow hot").

Related to heat (n.). With a long vowel in Middle English (rhyming with boat, wrote) which shortened in modern English, perhaps from influence of comparative hotter. As an adverb, Old English hote.

Hot as "full of sexual desire, lustful" is from c. 1500; the sense of "inciting desire" is 18c. Taste sense of "pungent, acrid, biting" is from 1540s. Sense of "exciting, remarkable, very good" is 1895; that of "stolen" is first recorded 1925 (originally with overtones of "easily identified and difficult to dispose of"); that of "radioactive" is from 1942. Of jazz music or combos from 1924.

Hot flashes in the menopausal sense attested from 1887. Hot stuff for anything good or excellent is by 1889, American English. Hot seat is from 1933. Hot potato in figurative sense is from 1846 (from being baked in the fire coals and pulled out hot). Hot cake is from 1680s; to sell like hot cakes is from 1839.

The hot and cold in hide-and-seek or guessing games (19c.) are from hunting (1640s), with notion of tracking a scent. Hot and bothered is by 1921. Hot under the collar in the figurative sense is from 1895.
hot air (n.): "unsubstantiated statements, boastful talk," 1900, from hot (adj.) + air (n.1). The adjectival phrase hot-air (of balloons, etc.) is from 1813.
hot dog (n.): also hotdog, "sausage on a split roll," c. 1890, American English, from hot (adj.) + dog (n.). Many early references are in college student publications; later popularized, but probably not coined, by cartoonist T.A. "Tad" Dorgan (1877-1929). It is said in early explanations to echo a suspicion (occasionally justified) that sausages contained dog meat.

Meaning "someone particularly skilled or excellent" (with overtones of showing off) is from 1896. Connection between the two senses, if any, is unclear. Hot dog! as an exclamation of approval was in use by 1906.
hot-dog, n. 1. One very proficient in certain things. 2. A hot sausage. 3. A hard student. 4. A conceited person. ["College Words and Phrases," in "Dialect Notes," 1900]
Related: Hot-dogger; hot-dogging.
hot pants (n.): "short-shorts," 1970, from hot (adj.) + pants (n.). Probably influenced by earlier sense of "sexual arousal" (1927).
hot spot (n.): also hotspot, 1888 as a skin irritation; 1931 as "nightclub;" 1938 in the firefighting sense; 1941 as "place of international conflict." See hot (adj.) + spot (n.).
hot water (n.): c. 1400, literal; 1530s in figurative sense of "trouble." See hot (adj.) + water (n.1). Hot-water bottle is from 1895.
hot-blooded (adj.): "passionate," 1590s; a relic of medieval physiology theory.
hot-foot (adv.): "hastily," c. 1300, from hot + foot (n.). As a verb in U.S. slang, from 1896. As the name of a prank played with matches, by 1934.
hot-rod (n.): also hot rod, 1945, American English, from hot (adj.) + rod (n.), here apparently in a sense of "hunk of metal" (the cars also were called hot iron).
hot-wire (v.): also hotwire, "bypass the ignition key to start a motor vehicle," 1966, from hot-wire (adj.), which is attested from 1889 in reference to electricity wires. Related: Hot-wired; hot-wiring.
hotbed (n.): also hot-bed, 1620s, "bed of earth heated by fermenting manure for growing early plants," from hot (adj.) + bed (n.). Generalized sense of "place that fosters rapid growth" is from 1768.
hotch-potch: see hodgepodge.
Hotchkiss (n.): 1878, type of machine gun named for its inventor, U.S. armaments-maker Benjamin B. Hotchkiss (1826-1885). In Japanese, the word for "stapler" is hotchikisu after the E. H. Hotchkiss Company of Norwalk, Connecticut, U.S., early and prominent manufacturer of staplers (incorporated 1895, name from 1897), which apparently was run by relatives of the gun inventor. The surname (attested from late 15c. as Hochekys) is a variant of Hodgkin.
hotel (n.): 1640s, "public official residence; large private residence," from French hôtel "a mansion, palace, large house," from Old French ostel, hostel "a lodging" (see hostel). Modern sense of "an inn of the better sort" is first recorded 1765. The same word as hospital.
hotelier (n.): "proprietor of a hotel," 1905, from French hôtelier "hotelkeeper," from Old French ostelier, hostelier (12c.), from hostel "a lodging" (see hostel). Compare hostler.
hothead (n.): "short-tempered person," 1650s, from hot in the figurative sense + head (n.); Johnson's dictionary also lists hotmouthed "headstrong, ungovernable;" Elizabethan English had hot-brain "hothead" (c. 1600); and Old English had hatheort "anger, rage," literally "hot heart."
hothouse (n.): mid-15c., "bath house," from hot + house (n.). In 17c. a euphemism for "brothel;" the meaning "glass-roofed structure for raising tender plants or protecting exotics" is from 1749. Figurative use of this sense by 1802.
hotly (adv.): in the literal sense 1520s, from hot (adj.) + -ly (2). Old English hatlice, Middle English hoteli are recorded only in the sense "ardently."
hotness (n.): 1520s, from hot (adj.) + -ness.
hotshot (n.): "important person," 1933; see hot + shot (n.). It earlier meant "fast train" (1925), and "foolish, reckless person" (c. 1600).
Hottentot (n.): 1670s, from South African Dutch, said in old Dutch sources to be a word that means "stammerer," from hot en tot "hot and tot," nonsense words imitative of stammering. The word was applied to the people for the clicking, jerking quality of Khoisan speech. Related: Hottentotic.
hottie (n.): also hotty, "attractive person," teen slang by 1995, from hot + -ie. The same word was used from 1947 with sense "hot water bottle."
Houdini (n.): "escape artist or other ingenious person," 1923, from Harry Houdini, professional name of U.S. escapist Erich Weiss (1874-1926).
hough (n.): see hock (n.1).
hound (n.): Old English hund "dog," from Proto-Germanic *hundas (source also of Old Saxon and Old Frisian hund, Old High German hunt, German Hund, Old Norse hundr, Gothic hunds), from PIE *kwnto-, dental enlargement of root *kwon- "dog" (see canine). Meaning narrowed 12c. to "dog used for hunting" (compare dog (n.)). Contemptuously, of a man, from late Old English.
hound (v.): "hunt with hounds," 1520s, from hound (n.). Figurative sense "pursue relentlessly" first recorded c. 1600. Related: Hounded; hounding.
hound-dog (n.): by 1821, from hound (n.) + dog (n.).
houndstooth (adj.): also hound's tooth, in reference to a jagged-edged design pattern, 1936, so called for resemblance.
houp-la (interj.): see hoopla.
hour (n.): c. 1200, "divine office prescribed for each of the seven canonical hours; the daily service at the canonical hours;" c. 1300, "time of day appointed for prayer, one of the seven canonical hours," from Old French ore, hore "canonical hour; one-twelfth of a day" (sunrise to sunset), from Latin hora "an hour;" poetically "time of year, season," from Greek hora a word used to indicate any limited time within a year, month, or day, from PIE *yor-a-, from root *yer- "year, season" (see year).

Church sense is oldest in English. Meaning "one of the 24 equal parts of a natural solar day (time from one sunrise to the next), equal hour; definite time of day or night reckoned in equal hours," and that of "one of the 12 equal parts of an artificial day (sunrise to sunset) or night, varying in duration according to the season; definite time of day or night reckoned in unequal hours" are from late 14c. In the Middle Ages the planets were held to rule over the unequal hours. As late as 16c. distinction sometimes was made in English between temporary (unequal) hours and sidereal (equal) ones. Meaning "time of a particular happening; the time for a given activity" (as in hour of death) is mid-14c.

The h- has persisted in this word despite not being pronounced since Roman times. Replaced Old English tid, literally "time" (see tide (n.)) and stund "period of time, point of time, hour" (compare German Stunde "hour"). German Uhr also is from French.

Greek hora could mean "a season; 'the season' (spring or summer)." In classical times it sometimes meant "a part of the day," such as morning, evening, noon, night. The Greek astronomers apparently borrowed the notion of dividing the day into twelve parts (mentioned in Herodotus) from the Babylonians. Night continued to be divided into four watches (see watch (n.)); but because the amount of daylight changed throughout the year, the hours were not fixed or of equal length.

As a measure of distance ("the distance that can be covered in an hour") it is recorded from 1785. At all hours "at all times" is from early 15c. For small hours (those with low numbers) see wee (adj.).
hourglass (n.): also hour-glass, instrument for measuring time, 1510s, from hour + glass (n.). Used 19c. in a variety of technical and scientific senses to describe the shape; in reference to women's torsos by 1897.
Men condemn corsets in the abstract, and are sometimes brave enough to insist that the women of their households shall be emancipated from them; and yet their eyes have been so generally educated to the approval of the small waist, and the hourglass figure, that they often hinder women who seek a hygienic style of dress. [Mary Ashton Rice Livermore, "The Story of My Life," 1898]
houri (n.): "nymph of Muslim paradise," 1737, from French houri (1650s), from Persian huri "nymph in Paradise," from Arabic haura "to be beautifully dark-eyed," like a gazelle + -i, Persian formative element denoting the singular.
hourlong (adj.): also hour-long, 1803, from hour + long (adj.).
hourly (adv.): late 15c., "every hour;" as an adjective, 1510s, "happening or done every hour," from hour + -ly.
house (n.): Old English hus "dwelling, shelter, building designed to be used as a residence," from Proto-Germanic *husan (source also of Old Norse, Old Frisian hus, Dutch huis, German Haus), of unknown origin, perhaps connected to the root of hide (v.) [OED]. In Gothic only in gudhus "temple," literally "god-house;" the usual word for "house" in Gothic being according to OED razn.

Meaning "family, including ancestors and descendants, especially if noble" is from c. 1000. Zodiac sense is first attested late 14c. The legislative sense (1540s) is transferred from the building in which the body meets. Meaning "audience in a theater" is from 1660s (transferred from the theater itself, playhouse). Meaning "place of business" is 1580s. The specialized college and university sense (1530s) also applies to both buildings and students collectively, a double sense found earlier in reference to religious orders (late 14c.). As a dance club DJ music style, probably from the Warehouse, a Chicago nightclub where the style is said to have originated.

To play house is from 1871; as suggestive of "have sex, shack up," 1968. House arrest first attested 1936. House-painter is from 1680s. House-raising (n.) is from 1704. On the house "free" is from 1889. House and home have been alliteratively paired since c. 1200.
And the Prophet Isaiah the sonne of Amos came to him, and saide vnto him, Thus saith the Lord, Set thine house in order: for thou shalt die, and not liue. [II Kings xx:1, version of 1611]
house (v.): "give shelter to," Old English husian "to take into a house; place or enclose in a house" (cognate with Old Frisian husa, German hausen, Dutch huizen); see house (n.). Intransitive sense from 1590s. Related: Housed; housing.
houseboat (n.): also house-boat, "boat fitted out as a house," 1790, from house (n.) + boat (n.).
housebreak (v.): 1820, "to break into a house criminally;" perhaps a back-formation from housebreaking or housebreaker. Sense of "to train a domestic animal to be clean in the house" is from 1881. Related: Housebroken.
housebreaking (n.): "breaking into a house with felonious intent," early 14c., from house (n.) + break (v.). Formerly used of crimes by day, burglary being for crimes by night. Modifying or replacing earlier husbreche, Old English hus-bryce. Housebreaker is from mid-15c.