Online Etymology Dictionary

unforgivable (adj.): 1540s, from un- (1) "not" + forgivable. In early use, especially with reference to the sin described in Matt. xii:31. Related: Unforgivably.
ungracious (adj.): c. 1200, "ungrateful;" early 14c., "lacking God's grace;" early 15c., "rude, unmannerly," from un- (1) "not" + gracious (adj.). Related: Ungraciously.
unmotivated (adj.): "lacking in motivation," by 1917, from un- (1) "not" + past participle of motivate. Meaning "lacking in motive" is attested from 1871. Unmotived is from 1794.
unmuzzled (adj.): c. 1600, from un- (1) "not" + past participle of muzzle (v.), or past participle of unmuzzle (v.), which is attested from c. 1600.
wussy (n.): 1960s, probably an alteration of pussy (n.2). DAS suggests shortened from hypothetical pussy-wussy, reduplicated form of pussy (n.1).
perch (v.): "to roost," late 14c., from Old French perchier "to sit on a perch" (of a bird), from perche (n.) (see perch (n.1)). Related: Perched; perching.
gobbler (n.): 1737, "turkey-cock," agent noun from gobble (v.2). As "one who eats greedily" 1755, from gobble (v.1).
Sheetrock (n.): 1921, proprietary name (claiming use from 1917) of a type of plaster wall-board, U.S. Gypsum Co., Chicago, Ill.; from sheet (n.1) + rock (n.).
popliteal (adj.): 1786, with -al (1) + Modern Latin popliteus (n.), 1704, short for popliteus (musculus), from poples "ham (of the leg)," which is of unknown origin.
hull (v.): "to remove the husk of," early 15c., from hull (n.1). Related: Hulled, which can mean both "having a particular kind of hull" and "stripped of the hull."
hack (v.3): "to cough with a short, dry cough," 1802, perhaps from hack (v.1) on the notion of being done with difficulty, or else imitative.
pressing (adj.): "exerting pressure," mid-14c., present participle adjective from press (v.1). Sense of "urgent, compelling, forceful" is from 1705. Related: Pressingly.
hypno-: word-forming element meaning "sleep," from Greek hypnos "sleep," from PIE *supno-, suffixed form of root *swep- (1) "to sleep" (see somnolence).
hideaway (n.): "small, secluded restaurant, etc.," 1929, from hide (v.1) + away. Earlier it meant "a fugitive person" (1871). Compare runaway, stowaway.
Hortense: fem. proper name, from Latin Hortensia, fem. of Hortensius, a Roman gens name, related to hortus "garden" (see yard (n.1)).
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.
handbill (n.): loose paper circulated by hand to make a public announcement, 1753, from hand (n.) + bill (n.1). Also applied to posted bills.
gudgeon (n.2): "pivot on the end of a beam," c. 1400, from Old French gojon "pin, peg, spike" (13c.), perhaps somehow an altered sense of gudgeon (n.1).
guide-post (n.): also guidepost, 1761, from guide (v.) + post (n.1). Placed at a fork or intersection, with signs to guide travelers on their way.
ephemeral (adj.): 1560s; see ephemera + -al (1). Originally of diseases and lifespans, "lasting but one day;" extended sense of "transitory" is from 1630s. Related: Ephemerally; ephemerality.
earful (n.): "a piece of one's mind," 1915, from ear (n.1) + -ful. Ear-bash (v.) is Australian slang (1944) for "talk inordinately" (to someone).
meddlesome (adj.): 1610s, from meddle + -some (1). Earlier was medlous "quarrelsome, meddlesome" (mid-15c.). Related: Meddlesomely. Character name Meddlesome Mattie attested from 1814.
irresistible (adj.): 1590s, from Late Latin irresistibilis, from assimilated form of in- "not, opposite of" (see in- (1)) + resistere (see resist). Related: Irresistibly; irresistibility.
benchmark (n.): also bench-mark, "surveyor's point of reference," 1838, from a specialized surveyors' use of bench (n.) + mark (n.1); figurative sense is from 1884.
peripheral (adj.): 1803, from periphery + -al (1). An earlier formation was peripherial (1670s). Related: Peripherally. As a noun, peripherals, "peripheral devices of a computer," is from 1966.
buck (v.): 1848, apparently with a sense of "jump like a buck," from buck (n.1). Related: Bucked; bucking. Buck up "cheer up" is from 1844.
erythema (n.): medical Latin, from Greek erythema "a redness on the skin; a blush; redness," from erythainein "to become red," from erythros "red" (see red (1)). Related: Erythematous.
frighten (v.): "strike with fear, terrify," 1660s, from fright (n.) + -en (1). Related: Frightened; frightening. The earlier verb was simply fright (v.).
experiential (adj.): 1640s (implied in experientially), from Latin experientia "knowledge gained by testing or trials" (see experience (n.)) + -al (1).
experimental (adj.): mid 15c., "having experience," from experiment (n.) + -al (1). Meaning "based on experiment" is from 1560s. Meaning "for the sake of experiment" is from 1792.
fearsome (adj.): "causing fear," 1768, from fear (n.) + -some (1). Occasionally used badly in the sense "timid," which ought to stick to fearful. Related: Fearsomely; fearsomeness.
flatten (v.): late 14c., "to prostrate oneself," also "to fall flat," from flat (adj.) + -en (1). Transitive meaning "to make flat" is 1620s. Related: Flattened; flattening.
flighty (adj.): 1550s, "swift," from flight (n.1) + -y (2). Sense of "fickle or frivolous" is from 1768, perhaps from notion of "given to 'flights' of imagination." Related: Flightiness.
flint-lock (n.): also flintlock, 1680s as a type of gunlock in which fire is produced by a flint striking the hammer, from flint + lock (n.1).
fatten (v.): 1550s, "to make fat," from fat + -en (1). Intransitive sense from 1630s. Related: Fattened; fattener. The earlier verb was simply fat (v.).
flypaper (n.): also fly-paper, 1851 (the thing itself is said to have become commonly available in London in 1848), from fly (n.1) + paper (n.).
inobservant (adj.): 1660s, from Late Latin inobservantem (nominative inobservans) "inattentive, negligent," from in- "not" (see in- (1)) + Latin observans (see observance). Related: Inobservance (1610s).
jerky (adj.): "characterized by jerks, spasmodic," 1819, originally in medical writing with reference to the pulse, from jerk (n.1) + -y (2). Related: Jerkily; jerkiness.
irresolvable (adj.): 1650s, "insoluble," from assimilated form of in- (1) "not, opposite of" + resolvable. Meaning "that cannot be resolved into parts" is from 1785. Related: Irresolvably.
inartistic (adj.): "not conformable to the rules or principles of art" [Century Dictionary], 1836, from in- (1) "not" + artistic. Inartistical is attested from 1849. Related: Inartistically.
clippers (n.): "shears-like cutting tool for hair, etc.," 1876, agent noun from clip (v.1). Earlier they were clipping shears (mid-15c.).
choreographer (n.): 1829, from choreography + -er (1). Choreographist (1857) did not thrive. In Greek, a person who trained a chorus was a khorodidaskelikos.
chummy (adj.): 1874, from chum (n.1) + -y (2). Related: Chumminess. Previously it was a noun, a common name for a chimney sweep, as a corruption of chinmey.
cardboard (n.): 1848, from card (n.) + board (n.1). Figurative sense is from 1893. An earlier word for the same stuff was card paper (1777).
dampen (v.): 1630s, "to dull or deaden" (of force, enthusiasm, ardor, etc.), from damp (adj.) + -en (1). Meaning "to moisten" is recorded from 1827. Related: Dampened; dampening.
costly (adj.): late 14c., from cost + -ly (1). Earlier formation with the same sense were costful (mid-13c.), costious (mid-14c.).
deaden (v.): 1660s "deprive of or diminish (some quality)," from dead (adj.) + -en (1). Earlier the verb was simply dead. Related: Deadened; deadening.
endometrium (n.): "lining membrane of the uterus," 1882, medical Latin, from endo- + Greek metra "uterus," related to meter (see mother (n.1)). Related: Endometrial (1870).
misplay (n.): 1889 in baseball context, from mis- (1) + play (n.). As a verb from 1824 (originally in music; 1842 in games). Related: Misplayed; misplaying.
electrical (adj.): 1630s, "giving off electricity when rubbed," from electric + -al (1). Meaning "relating to electricity, run by electricity" is from 1746. Related: Electrically.