Online Etymology Dictionary

neighbourhood: chiefly British English spelling of neighborhood; for spelling, see -or.
Neil: surname and masc. proper name, from Gaelic/Old Irish Niall "champion." Picked up by the Vikings in Ireland (as Njall), brought by them to Iceland and Norway, thence to France, from which place it was introduced in England at the Conquest. Incorrectly Latinized as Nigellus on mistaken association with niger "black," hence Nigel.
neither (conj.): Old English nawþer, contraction of nahwæþer, literally "not of two," from na "no" (see no) + hwæþer "which of two" (see whether). Spelling altered c. 1200 by association with either. Paired with nor from c. 1300; earlier with ne. Also used in Old English as a pronoun. As an adjective, mid-14c.
nekton: 1893, from German nekton (van Heusen, 1890), from Greek nekton, neuter of nektos "swimming," from nekhein "to swim" (see natatorium).
Nelly: fem. proper name, also Nellie, diminutive of Nell, a pet form of Ellen, Helen, or Eleanor. Meaning "weak-spirited person" is first attested 1961.
nelson (n.): type of wrestling hold, 1875, apparently from a proper or surname, but no one now knows whose.
Presently, Stubbs, the more skilful as well as the more powerful of the twain, seizes the luckless Jumper in a terrible gripe, known to the initiated as the Full Nelson. ["Lancashire Recreations," in "Chambers's Journal," April 24, 1875]
nem. con.: abbreviation of Latin phrase nemine contradicente "no one dissenting," hence, "without opposition."
nematocyst (n.): 1875, from nemato-, comb. form of Greek nema, nematos "thread" (genitive nematos), from stem of nein "to spin" (see needle (n.)) + cyst.
Nematoda: a class of worms, Modern Latin compound of nemat- "thread" (from Greek nema, genitive nematos "thread," from stem of nein "to spin;" see needle (n.)) + -odes "like, of the nature of" (see -oid).
nematode (n.): 1865, from Modern Latin Nematoda, the class or phylum name.
Nembutal: type of barbiturate, 1930, proprietary name of pentobarbitone sodium, formed from letters and syllables from N(a) "sodium" + full chemical name 5-ethyl-5-1-methylbutyl barbiturate.
Nemean (adj.): 1580s, "pertaining to Nemea," a wooded valley in Argolis, especially in reference to the lion there, said to have been killed by Herakles. The place name is from Greek nemos "grove."
nemesis: 1570s, Nemesis, "Greek goddess of vengeance, personification of divine wrath," from Greek nemesis "just indignation, righteous anger," literally "distribution" (of what is due), related to nemein "distribute, allot, apportion one's due," from PIE root *nem- "to divide, distribute, allot, to take" (source also of Old English, Gothic niman "to take," German nehmen; see nimble). With a lower-case -n-, in the sense of "retributive justice," attested from 1590s. General sense of "anything by which it seems one must be defeated" is 20c.
nemo (n.): Latin, literally "no man, no one, nobody."
neo-: word-forming element meaning "new, recent," used in a seemingly endless number of adjectives and nouns, mostly coined since c. 1880, from Greek neo-, comb. form of neos "new, young, youthful; fresh, strange; lately, just now," from PIE root *newo- (see new).
neo-classical: also neoclassical, style of art, architecture, etc., influenced by classical patterns, 1859, especially in reference to 18th century English literature; from neo- + classical. Related: Neo-classicism/neoclassicism.
neo-conservative (n.): also neoconservative; used in the modern sense by 1979:
My Republican vote [in the 1972 presidential election] produced little shock waves in the New York intellectual community. It didn't take long - a year or two - for the socialist writer Michael Harrington to come up with the term "neoconservative" to describe a renegade liberal like myself. To the chagrin of some of my friends, I decided to accept that term; there was no point calling myself a liberal when no one else did. [Irving Kristol, "Forty Good Years," "The Public Interest," Spring 2005]
The term is attested from 1960, but it originally often was applied to Russell Kirk and his followers, who would be philosophically opposed to the later neocons. From neo- + conservative.
neo-liberal: also neoliberal, 1966, from neo- + liberal. Related: Neoliberalism.
neo-natal (adj.): also neonatal, 1883, from neo- + natal.
neocolonialism (n.): also neo-colonialism, 1955, from neo- + colonialism.
neocon (n.): by 1987, abbreviation for neo-conservative in the U.S. political sense.
Neoconservatism is the first variant of American conservatism in the past century that is in the 'American grain.' It is hopeful, not lugubrious; forward-looking, not nostalgic; and its general tone is cheerful, not grim or dyspeptic. Its 20th-century heroes tend to be TR, FDR, and Ronald Reagan. Such Republican and conservative worthies as Calvin Coolidge, Herbert Hoover, Dwight Eisenhower, and Barry Goldwater are politely overlooked. [Irving Kristol, "The Neoconservative Persuasion," in "The Weekly Standard," Aug. 25, 2003]
neolithic (adj.): "pertaining to the later Stone Age," 1865, coined by John Lubbock, later Baron Avebury, (1834-1913) from neo- + -lith "stone."
neolocal (adj.): 1949, from neo- + local (adj.).
neologism (n.): "practice of innovation in language," 1772 (in a translation from French), from French néologisme, from neo- (see neo-) + Greek logos "word" (see lecture (n.)) + -ism. Meaning "new word or expression" is from 1803. Neological is attested from 1754.
neon (n.): 1898, coined by its discoverers, Sir William Ramsay and Morris W. Travers, from Greek neon, neuter of neos "new" (see new); so called because it was newly discovered. Neon sign is attested from 1927.
neonate (n.): "recently born infant," 1905, coined from neo- + Latin natus "born," past participle of nasci "be born" (Old Latin gnasci; see genus).
neonatology (n.): branch of medicine concerned with newborn infants, 1960, from neonate "recently born infant" + -ology.
neophyte (n.): "new convert," 1550s, from Church Latin neophytus, from Greek neophytos "a new convert," noun use of adjective meaning "newly initiated, newly converted," literally "newly planted," from neos "new" (see new) + phytos "grown; planted," verbal adjective of phyein "cause to grow, beget, plant" (see physic). Church sense is from I Tim. iii:6. Rare before 19c. General sense of "one who is new to any subject" is first recorded 1590s.
neoplasia (n.): 1868, from neo- + -plasia.
neoplasm (n.): 1864, coined in German by Karl Friedrich Burdach (1776-1847) from neo- + Greek plasma "formation" (see -plasm). Related: Neoplastic.
Neoplatonism (n.): also Neo-platonism, 1827, a philosophical and religious system mixing Platonic ideas and oriental mysticism, originating 3c. at Alexandria, especially in writings of Plotinus, Porphyry, and Proclus. Neoplatonian is attested from 1831. Related: Neoplatonic; Neoplatonist.
neoteny (n.): retention of juvenile characteristics in adult life, 1901, from German neotenie (1884), from Greek neos "young" (see new) + teinein "to extend" (see tenet).
neoteric (adj.): "recent, new," 1590s, from Late Latin neotericus, from Greek neoterikos "youthful, fresh, modern," from neoteros, comp. of neos "new" (see new). Related: Neoterism.
Nepal: from Sanskrit Nepala, said to be from nipat "to fly down" (from ni "down" + pat "to fly") + alaya "abode, house." If this is right, the reference would be to villages in mountain vales. Related: Nepalese.
nepenthe (n.): 1570s, nepenthes, from Greek nepenthes, from ne- "no, not" (see un-) + penthos "pain, grief," from PIE *kwent(h)- "to suffer" (see pathos). A drug of Egypt mentioned in the "Odyssey" as capable of banishing grief or trouble from the mind. The -s is a proper part of the word, but likely was mistaken in English as a plural affix and dropped.
nephew (n.): c. 1300, from Old French neveu (Old North French nevu) "grandson, descendant," from Latin nepotem (nominative nepos) "sister's son, grandson, descendant," in post-Augustan Latin, "nephew," from PIE *nepot- "grandchild," and in a general sense, "male descendant other than son" (source also of Sanskrit napat "grandson, descendant;" Old Persian napat- "grandson;" Old Lithuanian nepuotis "grandson;" Dutch neef; German Neffe "nephew;" Old Irish nia, genitive niath "son of a sister," Welsh nei). Used in English in all the classical senses until meaning narrowed in 17c., and also as a euphemism for "the illegitimate son of an ecclesiastic" (1580s). The Old English cognate, nefa "nephew, stepson, grandson, second cousin" survived to 16c.
Nephilim: of uncertain etymology; much disputed.
The only obvious meaning of this Hebrew term is "fallen ones" -- perhaps, those who have come down from the realm of the gods; but then the word might conceivably reflect an entirely different, un-Hebraic background. [Robert Alter, "The Five Books of Moses," 2004]
nephrectomy (n.): 1880, from nephro- "kidney" + -ectomy "a cutting out."
nephridium (n.): (plural nephridia), 1877, Modern Latin, from Greek diminutive of nephros "kidney" (see nephron).
nephritis (n.): 1570s, from Late Latin nephritis, from Greek nephritis "disease of the kidneys," from nephros "kidney" (see nephron) + -itis "inflammation." Related: Nephritic.
nephro-: before vowels nephr-, word-forming element meaning "kidney, kidneys," from nephro-, comb. form of Greek nephros "kidney" (see nephron).
nephrolithiasis (n.): 1837, probably from German, from nephro- + lithos "stone" (see litho-) + -iasis "pathological or morbid condition."
nephrology (n.): 1839, from nephro- + -ology. Related: Nephrologist.
nephron (n.): 1932, from German nephron (1924), from Greek nephros "kidney," from PIE *negwhro- "kidney" (source also of Latin nefrones, Old Norse nyra, Dutch nier, German Niere "kidney").
nepotism (n.): "favoritism shown to relatives, especially in appointment to high office," 1660s, from French népotisme (1650s), from Italian nepotismo, from nepote "nephew," from Latin nepotem (nominative nepos) "grandson, nephew" (see nephew). Originally, practice of granting privileges to a pope's "nephew" which was a euphemism for his natural son.
Neptune: late 14c., "god of the sea," from Latin Neptunus, son of Saturn, brother of Jupiter, the Roman god of the sea (later identified with Greek Poseidon), probably from PIE root *nebh- "cloud" (source of Latin nebula "fog, mist, cloud;" see nebula), via a sense of "moist, wet." The planet so named was discovered by Galle in 1846. Until the identification of Pluto in 1930, it was the most distant planet known.
Neptunian (adj.): 1650s as "pertaining to the god Neptune;" 1794 in the geological sense, referring to actions of water, from Neptune + -ian. Usually opposed to volcanic or plutonic. As a noun meaning "inhabitant of the planet Neptune" it is recorded from 1870.
neptunium (n.): 1941, from Neptune + element ending -ium. Named for its relative position in the periodic table, next after Uranium, as the planet Neptune is one beyond Uranus. See also plutonium.
nerd (n.): 1951, U.S. student slang, probably an alteration of 1940s slang nert "stupid or crazy person," itself an alteration of nut. The word turns up in a Dr. Seuss book from 1950 ("If I Ran the Zoo"), which may have contributed to its rise.
nerdy (adj.): 1978, from nerd + -y (2). Related: Nerdiness.