sigh (v.) Look up sigh at Dictionary.com
mid-13c., probably a Middle English back-formation from sighte, past tense of Old English sican "to sigh," perhaps echoic of the sound of sighing. Related: Sighed; sighing.
sigh (n.) Look up sigh at Dictionary.com
early 14c., from sigh (v.).
sight (n.) Look up sight at Dictionary.com
Old English sihð, gesiht, gesihð "thing seen; faculty of sight; aspect; vision; apparition," from Proto-Germanic *sekh(w)- (cognates: Danish sigte, Swedish sigt, Middle Dutch sicht, Dutch zicht, Old High German siht, German Sicht, Gesicht), stem that also yielded Old English seon (see see (v.)), with noun suffix -th (2), later -t.
Verily, truth is sight. Therefore if two people should come disputing, saying, 'I have seen,' 'I have heard,' we should trust the one who says 'I have seen.' [Brhadaranyaka Upanishad 5.14.4]
Meaning "perception or apprehension by means of the eyes" is from early 13c. Meaning "device on a firearm to assist in aiming" is from 1580s. A "show" of something, hence, colloquially, "a great many; a lot" (late 14c.). Sight for sore eyes "welcome visitor" is attested from 1738; sight unseen "without previous inspection" is from 1892. Sight gag first attested 1944. Middle English had sighty (late 14c.) "visible, conspicuous; bright, shining; attractive, handsome;" c.1400 as "keen-sighted;" mid-15c. as "discerning" (compare German sichtig "visible").
sight (v.) Look up sight at Dictionary.com
1550s, "look at, view, inspect," from sight (n.). From c.1600 as "get sight of," 1842 as "take aim along the sight of a firearm." Related: Sighted; sighting.
sighting (n.) Look up sighting at Dictionary.com
"instance of catching sight," 1853, verbal noun from sight (v.).
sightless (adj.) Look up sightless at Dictionary.com
late 13c., from sight (n.) + -less. Related: Sightlessly; sightlessness.
sights (n) Look up sights at Dictionary.com
"features of a place that are deemed worth seeing," 1630s, plural of sight (n.).
sightseeing (n.) Look up sightseeing at Dictionary.com
also sight-seeing, 1821, from sight (see sights) + present participle of see (v.). Sight-see (v.) is from 1824. Sight-seer first recorded 1821.
sigil (n.) Look up sigil at Dictionary.com
"a sign, mark, or seal," mid-15c., from Late Latin sigillum, from Latin sigilla (neuter plural) "statuettes, little images, seal," diminutive of signum "sign" (see sign (n.)). In astrology, an occult device supposed to have great power (1650s).
When my mistress died, she had under her arm-hole a small scarlet bag full of many things, which, one that was there delivered unto me. There was in this bag several sigils, some of Jupiter in Trine, others of the nature of Venus, some of iron, and one of gold, of pure angel-gold, of the bigness of a thirty-three shilling piece of King James's coin. ["The Antiquarian Repertory," London, 1780]
Sigismund Look up Sigismund at Dictionary.com
masc. proper name, from German, literally "protection through victory," from Old High German sigu "victory" (see Siegfried) + munt "hand, protection," from PIE *man- "hand" (see manual (adj.)).
sigma Look up sigma at Dictionary.com
18th letter of the Greek alphabet, corresponding to Latin S, a metathesis of Hebrew samekh. In uncial writing, shaped like an S or a C.
sigmatism (n.) Look up sigmatism at Dictionary.com
1888, "difficulty in pronouncing 'S,'" from comb. form of sigma + -ism. As "use or recurrence of 'S'" from 1889.
sigmoid (adj.) Look up sigmoid at Dictionary.com
"shaped like a C" (1660s) or "shaped like an S" (1786), from sigma (q.v.) + -oid. Especially of the flexure of the colon (1891).
sigmoidoscopy (n.) Look up sigmoidoscopy at Dictionary.com
1896, from sigmoid + -scopy, with connective -o-.
sign (n.) Look up sign at Dictionary.com
early 13c., "gesture or motion of the hand," especially one meant to communicate something, from Old French signe "sign, mark," from Latin signum "identifying mark, token, indication, symbol; proof; military standard, ensign; a signal, an omen; sign in the heavens, constellation," according to Watkins, literally "standard that one follows," from PIE *sekw-no-, from root *sekw- (1) "to follow" (see sequel).

Ousted native token. Meaning "a mark or device having some special importance" is recorded from late 13c.; that of "a miracle" is from c.1300. Zodiacal sense in English is from mid-14c. Sense of "characteristic device attached to the front of an inn, shop, etc., to distinguish it from others" is first recorded mid-15c. Meaning "token or signal of some condition" (late 13c.) is behind sign of the times (1520s). In some uses, the word probably is a shortening of ensign. Sign language is recorded from 1847; earlier hand-language (1670s).
sign (v.) Look up sign at Dictionary.com
c.1300, "to make the sign of the cross," from Old French signier "to make a sign (to someone); to mark," from Latin signare "to set a mark upon, mark out, designate; mark with a stamp; distinguish, adorn;" figuratively "to point out, signify, indicate," from signum (see sign (n.)). Sense of "to mark, stamp" is attested from mid-14c.; that of "to affix one's name" is from late 15c. Meaning "to communicate by hand signs" is recorded from 1700. Related: Signed; signing.
sign-in (n.) Look up sign-in at Dictionary.com
1968, from the verbal phrase; see sign (v.) + in (adv.).
sign-up (n.) Look up sign-up at Dictionary.com
"number who have signed up," 1926, from the verbal phrase; see sign (v.) + up (adv.).
signage (n.) Look up signage at Dictionary.com
1972, in reference to signs on roads or outside stores, from sign (n.) + -age. Earlier in legal language with reference to affixing signatures.
signal (n.) Look up signal at Dictionary.com
late 14c., "visible sign, indication," from Old French signal, seignal "seal, imprint, sign, mark," from Medieval Latin signale "a signal," from Late Latin signalis (adj.) "used as a signal, pertaining to a sign," from Latin signum "signal, sign" (see sign (n.)). Restricted sense "agreed-upon sign (to commence or desist, etc.) is from 1590s. Meaning "modulation of an electric current" is from 1855.
signal (v.) Look up signal at Dictionary.com
1805, "to make signals to," from signal (n.). Related: Signaled; signaling. Earlier verb was signalize (1650s).
signal (adj.) Look up signal at Dictionary.com
"remarkable, striking, notable" ("serving as a sign"), 1640s, from French signalé, past participle of signaler "to distinguish, signal" (see signal (n.)).
signatory (adj.) Look up signatory at Dictionary.com
1640s, "used in sealing," from Latin signatorius "of sealing," from signatus, past participle of signare "to sign" (see sign (v.)). Noun sense of "one who signs" (a treaty, etc.) first recorded 1866.
signature (n.) Look up signature at Dictionary.com
1530s, a kind of document in Scottish law, from Middle French signature (16c.) or directly from Medieval Latin signatura "signature, a rescript," in classical Latin "the matrix of a seal," from signatus, past participle of signare "to mark with a stamp, sign" (see sign (v.)).

Meaning "one's own name written in one's own hand" is from 1570s, replacing sign-manual (early 15c.) in this sense. Musical sense of "signs placed it the beginning of a staff to indicate the key and rhythm" is from 1806. Meaning "a distinguishing mark of any kind" is from 1620s.
signboard (n.) Look up signboard at Dictionary.com
also sign-board, 1630s, from sign (n.) + board (n.1).
signee (n.) Look up signee at Dictionary.com
1953, from sign (v.) + -ee.
signer (n.) Look up signer at Dictionary.com
1610s, agent noun from sign (v.). In American history, with reference to the Declaration of Independence, by 1865.
signet (n.) Look up signet at Dictionary.com
late 14c., "small seal" (especially one on a finger ring), from Old French signet "a small seal," diminutive of signe "sign" (see sign (n.)).
significance (n.) Look up significance at Dictionary.com
c.1400, "meaning," from Old French significance or directly from Latin significantia "meaning, force, energy," from significans, present participle of significare "to mean, import, signify" (see signify). The earlier word was signifiance (mid-13c.). Meaning "importance" is from 1725. Related: Significancy.
significant (adj.) Look up significant at Dictionary.com
1570s, "having a meaning," from Latin significantem (nominative significans, present participle of significare "make known, indicate" (see signify). Earlier in the same sense was significative (c.1400). Often "having a special or secret meaning," hence "important" (1761). Related: Significantly. Significant figure is from 1680s. Significant other (n.) attested by 1961, in psychology, "the most influential other person in the patient's world."
signification (n.) Look up signification at Dictionary.com
early 14c., "symbolization, representation," from Old French significacion and directly from Latin significationem (nominative significatio) "a signifying, indication, expression, sign, token, meaning, emphasis," noun of action from past participle stem of significare "make known, indicate" (see signify). From late 14c. as "meaning" (of a word, etc.).
signifier (n.) Look up signifier at Dictionary.com
1530s, agent noun from signify. In U.S. black use by 1962.
signify (v.) Look up signify at Dictionary.com
late 13c., "be a sign of, indicate, mean," from Old French signifier (12c.), from Latin significare "to make signs, show by signs, point out, express; mean, signify; foreshadow, portend," from significus (adj.), from signum "sign" (see sign (n.)) + root of facere "to make" (see factitious). Intransitive sense of "to be of importance" is attested from 1660s. Meaning "engage in mock-hostile banter" is American English black slang first recorded 1932.
...'signifying,' which in Harlemese means making a series of oblique remarks apparently addressed to no one in particular, but unmistakable in intention in such a close-knit circle. ["Down Beat," March 7, 1968]
signor (n.) Look up signor at Dictionary.com
an Italian lord or gentleman, 1570s, from Italian signore, from Latin seniorem, accusative of senior (see senior (adj.)). Feminine form signora is from 1630s; diminutive signorina is first recorded 1820.
signpost (n.) Look up signpost at Dictionary.com
also sign-post, 1610s, "sign on a post, usually indicating an inn or shop," from sign (n.) + post (n.1). Meaning "guide- or direction-post along a road" is attested from 1863. Figurative sense is from 1889.
sike (n.) Look up sike at Dictionary.com
also syke, "small stream," a Scottish and Northern word, from Old English sic or cognate Old Norse sik "a ditch, trench."
Sikh (n.) Look up Sikh at Dictionary.com
1781, member of a politico-religious community established c.1500 in Punjab by Nanak Shah, from Hindi sikh "disciple," from Sanskrit siksati "studies, learns," related to saknoti "he is able, he is strong" (see Shakti).
Sikhism (n.) Look up Sikhism at Dictionary.com
"tenets of the Sikhs," 1849, from Sikh + -ism.
silage (n.) Look up silage at Dictionary.com
"fodder packed in a silo," 1884, alteration (probably by influence of silo) of ensilage.
Silas Look up Silas at Dictionary.com
masc. proper name, from Late Latin, from Greek Silas, contraction of Silouanos, transliteration of Latin Silvanus, a name that literally means "living in the woods," from silva "wood" (see sylvan).
silence (n.) Look up silence at Dictionary.com
c.1200, "muteness, state of being silent," from Old French silence "state of being silent; absence of sound," from Latin silentium "a being silent," from silens, present participle of silere "be quiet or still," of unknown origin. Meaning "absence of sound" in English is from late 14c.
silence (v.) Look up silence at Dictionary.com
1560s, intransitive, "become still or silent;" 1590s, transitive, "make silent," from silence (n.). Related: Silenced; silencing.
silencer (n.) Look up silencer at Dictionary.com
c.1600, "person who silences," agent noun from silence (v.). Meaning "mechanism that stifles the sound of a motor or firearm" is from 1898.
silent (adj.) Look up silent at Dictionary.com
c.1500, "without speech, silent, not speaking," from Latin silentem (nominative silens) "still, calm, quiet," present participle of silere "be quiet or still" (see silence (n.)). Meaning "free from noise or sound" is from 1580s.

Of letters, c.1600; of films, 1914. In the looser sense "of few words," from 1840. Phrase strong, silent (type) is attested from 1905. Silent majority in the political sense of "mass of people whose moderate views are not publicly expressed and thus overlooked" is first attested 1955 in a British context and was used by John F. Kennedy but is most associated in U.S. with the rhetoric of the Nixon administration (1969-74).
It is time for America's silent majority to stand up for its rights, and let us remember the American majority includes every minority. America's silent majority is bewildered by irrational protest. [Spiro T. Agnew, May 9, 1969]
In Victorian use, the phrase meant "the dead" (1874; compare Roman use of the noun plural of "silent" to mean "the dead"). Silence is golden (1831) is Carlyle's translation ["Sartor Resartus"] of part of the "Swiss Inscription" Sprechen ist silbern, Schweigen ist golden. In one 14c. text Latin "one who is silent" is translated by a beere stille.
silently (adv.) Look up silently at Dictionary.com
1560s, from silent (adj.) + -ly (2).
Silenus Look up Silenus at Dictionary.com
1710, from Greek Seilenos, foster-father of Bacchus and leader of the satyrs; the name is of unknown origin (Klein compares Thracian zilai "wine").
Silesia Look up Silesia at Dictionary.com
former eastern German province, now southwestern Poland, from Latinized form of German Schliesen (Polish Śląsk), from the name of a river and a mountain there, from Silingi or Silingae, name of a Vandalic (Germanic) people who supposedly had a religious center at the mountain. Related: Silesian. In reference to cloth imported from there from 1670s, especially "a thin cotton cloth, commonly twilled, used for linings for women's dresses and men's garments."
silhouette (n.) Look up silhouette at Dictionary.com
1798, from French silhouette, in reference to Étienne de Silhouette (1709-1767), French minister of finance in 1759. Usually said to be so called because it was an inexpensive way of making a likeness of someone, a derisive reference to Silhouette's petty economies to finance the Seven Years' War, which were unpopular among the nobility. But other theories are that it refers to his brief tenure in office, or the story that he decorated his chateau with such portraits.
Silhouette portraits were so called simply because they came into fashion in the year (1759) in which M. de Silhouette was minister. [A. Brachet, "An Etymological Dictionary of the French Language," transl. G.W. Kitchin, 1882]
Used of any sort of dark outline or shadow in profile from 1843. The verb is recorded from 1876, from the noun. The family name is a Frenchified form of a Basque surname; Arnaud de Silhouette, the finance minister's father, was from Biarritz in the French Basque country; the southern Basque form of the name would be Zuloeta or Zulueta, which contains the suffix -eta "abundance of" and zulo "hole" (possibly here meaning "cave").
silica (n.) Look up silica at Dictionary.com
"hard silicon dioxide," 1801, Modern Latin, from Latin silex (genitive silicis) "flint, pebble," on model of alumina, soda.
silicate (n.) Look up silicate at Dictionary.com
1811, from silica + -ate (3).