sect (n.)
mid-14c., "distinctive system of beliefs or observances; party or school within a religion," from Old French secte, sete "sect, religious community," or directly from Late Latin secta "religious group, sect in philosophy or religion," from Latin secta "manner, mode, following, school of thought," literally "a way, road, beaten path," from fem. of sectus, variant past participle of sequi "follow," from PIE *sekw- (1) "to follow" (see sequel). Confused in this sense with Latin secta, fem. past participle of secare "to cut" (see section (n.)). Meaning "separately organized religious body" is recorded from 1570s.
sectarian (adj.)
1640s, originally applied by Presbyterians to Independents, from Medieval Latin sectarius, from secta (see sect).
sectarianism (n.)
1670s, "disposition to petty sects in opposition to things established" [Johnson]; see sectarian + -ism.
sectary (n.)
"member or adherent of a sect," 1550s, from French sectaire or directly from Medieval Latin sectarius, from secta (see sect).
section (n.)
late 14c., "intersection of two straight lines; division of a scale;" from Old French section or directly from Latin sectionem (nominative sectio) "a cutting, cutting off, division," noun of action from past participle stem of secare "to cut," from PIE root *sek- "to cut" (cognates: Old Church Slavonic seko, sešti "to cut," se čivo "ax, hatchet;" Lithuanian isekti "to engrave, carve;" Albanian šate "mattock;" Old Saxon segasna, Old English sigðe "scythe;" Old English secg "sword," seax "knife, short sword;" Old Irish doescim "I cut;" Latin saxum "rock, stone").

From 1550s as "act of cutting or dividing." Meaning "subdivision of a written work, statute, etc." is from 1570s. Meaning "a part cut off from the rest" is from early 15c.
section (v.)
"divide into sections," 1819, from section (n.). Related: Sectioned; sectioning.
sectional (adj.)
1806; see section (n.) + -al (1). Noun meaning "piece of furniture composed of sections which can be used separately" is attested by 1961, from sectional seat, sectional sofa, etc. (1949).
sectionalism (n.)
1836, American English, from sectional + -ism. In frequent use from 1856.
sector (n.)
1560s, "section of a circle between two radii," from Late Latin sector "section of a circle," in classical Latin "a cutter, one who cuts," from sectus, past participle of secare "to cut" (see section (n.)). Translated Greek tomeus in Latin editions of Archimedes. Meaning "area, division" appeared 1920, generalized from military sense (1916) of "part of a front," based on a circle centered on a headquarters. As a verb from 1884. Related: Sectoral; sectorial.
secular (adj.)
c.1300, "living in the world, not belonging to a religious order," also "belonging to the state," from Old French seculer (Modern French séculier), from Late Latin saecularis "worldly, secular, pertaining to a generation or age," from Latin saecularis "of an age, occurring once in an age," from saeculum "age, span of time, generation."

According to Watkins, this is probably from PIE *sai-tlo-, with instrumental element *-tlo- + *sai- "to bind, tie" (see sinew), extended metaphorically to successive human generations as links in the chain of life. Another theory connects it with words for "seed," from PIE root *se- "to sow" (see sow (v.), and compare Gothic mana-seþs "mankind, world," literally "seed of men").

Used in ecclesiastical writing like Greek aion "of this world" (see cosmos). It is source of French siècle. Ancient Roman ludi saeculares was a three-day, day-and-night celebration coming once in an "age" (120 years). In English, in reference to humanism and the exclusion of belief in God from matters of ethics and morality, from 1850s.
secularism (n.)
"doctrine that morality should be based on the well-being of man in the present life, without regard to religious belief or a hereafter," 1846, from secular + -ism.
secularist (n.)
1846, "one who theoretically rejects and ignores all forms of religion based on revelation;" see secularism + -ist. From 1851 as "one who maintains that public education and civil policy should be conducted without the introduction of a religious element." Related: Secularistic.
secularization (n.)
1706, "conversion to secular purposes," in reference to Church property; see secularize + -ation. General use by 1863.
secularize (v.)
1610s, of property, offices, etc., from secular + -ize. From 1711 as "to become worldly;" from 1846 of education, social institutions, etc. Related: Secularized; secularizing.
secundine (n.)
"afterbirth," from Late Latin secundinae (plural), from Latin secundae "the afterbirth," shortened from secundae membranae, literally "the second membranes," from secundus "second" (see second (adj.)). Related: Secundines.
secure (adj.)
1530s, "without care, dreading no evil," from Latin securus, of persons, "free from care, quiet, easy," also in a bad sense, "careless, reckless;" of things, "tranquil; free from danger, safe," from *se cura, from se "free from" (see secret (n.)) + cura "care" (see cure (n.)).

In English, of places, "free from danger, unexposed," from 1580s. Meaning "firmly fixed" (of material things) is from 1841, on notion of "affording grounds for confidence." Of telephones, "not wiretapped," from 1961. Replaced Middle English siker, from Old English sicor, from the Latin word. Related: Securely.
secure (v.)
c.1600, "to make safe," from secure (adj.). Meaning "ensure, make certain" is from 1650s; that of "seize and hold" is from 1640s; sense of "get possession" is from 1743. Related: Secured; securing.
security (n.)
mid-15c., "condition of being secure," from Latin securitas, from securus "free from care" (see secure). Replacing sikerte (early 15c.), from an earlier borrowing from Latin; earlier in the sense "security" was sikerhede (early 13c.); sikernesse (c.1200).

Meaning "something which secures" is from 1580s; "safety of a state, person, etc." is from 1941. Legal sense of "property in bonds" is from mid-15c.; that of "document held by a creditor" is from 1680s. Phrase security blanket in figurative sense is attested from 1966, in reference to the crib blanket carried by the character Linus in the "Peanuts" comic strip (1956).
sedan (n.)
1630s, "covered chair on poles," possibly from a southern Italian dialect derivative of Italian sede "chair" (compare Italian seggietta, 1590s; the thing itself was said to have been introduced from Naples), from Latin sedes, related to sedere "sit" (see sedentary). Since Johnson's conjecture, often derived from the town of Sedan in France, where it was said to have been made or first used, but historical evidence for this is lacking.

Introduced in England by Sir Sanders Duncombe in 1634 and first called a covered chair. "In Paris the sedan-chair man was usually an Auvergnat, in London an Irishman" ["Encyclopaedia Britannica," 1929]. Meaning "closed automobile seating four or more" first recorded 1912, American English.
sedate (v.)
"treat with sedatives," 1945, a back-formation from the noun derivative of sedative (adj.). The word also existed 17c. in a sense "make calm or quiet." Related: Sedated; sedating.
sedate (adj.)
"calm, quiet," 1660s, from Latin sedatus "composed, moderate, quiet, tranquil," past participle of sedare "to settle, calm," causative of sedere "to sit" (see sedentary). Related: Sedately.
sedation (n.)
early 15c., "alleviation of pain;" 1540s, "act of making calm," from Middle French sédation and directly from Latin sedationem (nominative sedatio) "a quieting, assuaging, a calming," noun of action from past participle stem of sedare (see sedate (adj.)).
sedative (adj.)
"tending to calm or soothe," early 15c., from Medieval Latin sedativus "calming, allaying," from sedat-, past participle stem of sedare, causative of sedere "to sit" (see sedentary). The noun derivative meaning "a sedative drug" is attested from 1785. Hence, "whatever soothes or allays."
sedentary (adj.)
1590s, "remaining in one place," from Middle French sédentaire (16c.) and directly from Latin sedentarius "sitting, remaining in one place," from sedentem (nominative sedens), present participle of sedere "to sit; occupy an official seat, preside; sit still, remain; be fixed or settled," from PIE root *sed- (1) "to sit" (cognates: Sanskrit a-sadat "sat down," sidati "sits;" Old Persian hadis "abode;" Greek ezesthai "to sit," hedra "seat, chair, face of a geometric solid;" Old Irish suide "seat, sitting;" Welsh sedd "seat," eistedd "sitting;" Old Church Slavonic sežda, sedeti "to sit;" Lithuanian sedmi "to sit;" Russian sad "garden," Lithuanian soditi "to plant;" Gothic sitan, Old English sittan "to sit;" see sit). Of persons, the sense "not in the habit of exercise" is recorded from 1660s.
Seder (n.)
home service on the first nights of Passover, 1865, from Hebrew sedher "order, procedure," related to sedherah "row, rank."
sederunt (n.)
"sitting, session," Latin, literally "they sat" (typical opening word in recordings of such proceedings), third person plural past tense of sedere "to sit" (see sedentary).
sedge (n.)
"coarse grass-like plant growing in wet places," Old English secg "sedge, reed, rush," from Proto-Germanic *sagjoz (cognates: Low German segge, German Segge), probably from PIE root *sek- "to cut" (see section (n.) and compare Old English secg, identical in form but meaning "sword;" and German schwertel-gras "sedge" from schwert "sword"), on notion of plant with "cutting" leaves (compare etymological sense of gladiolus). Old Irish seisg, Welsh hesgreed "rush" might represent a similar sense development from the same root. Often spelled seg, segg until present form triumphed early 1900s.
sediment (n.)
1540s, "matter which settles at the bottom of water or other liquid," from Middle French sédiment (16c.) and directly from Latin sedimentum "a settling, sinking down," from stem of sedere "to settle, sit" (see sedentary).
sedimentary (adj.)
1764, from sediment + -ary. Sedimentary rock attested by 1830 (in Lyell). Sedimental (adj.) is recorded from c.1600.
sedimentation (n.)
1845, from sediment + -ation.
sedition (n.)
mid-14c., "rebellion, uprising, revolt, concerted attempt to overthrow civil authority; violent strife between factions, civil or religious disorder, riot; rebelliousness against authority," from Old French sedicion (14c., Modern French sédition) and directly from Latin seditionem (nominative seditio) "civil disorder, dissention, strife; rebellion, mutiny," literally "a going apart, separation," from se- "apart" (see secret) + itio "a going," from past participle of ire "to go" (see ion).

Meaning "conduct or language inciting to rebellion against a lawful government" is from 1838. An Old English word for it was folcslite. Less serious than treason, as wanting an overt act, "But it is not essential to the offense of sedition that it threaten the very existence of the state or its authority in its entire extent" [Century Dictionary].
seditious (adj.)
mid-15c., from Middle French seditieux, from Latin seditiosus "full of discord, factious, mutinous," from seditio (see sedition). Related: Seditiously; seditiousness.
seduce (v.)
1520s, "to persuade a vassal, etc., to desert his allegiance or service," from Latin seducere "lead away, lead astray," from se- "aside, away" (see secret (n.)) + ducere "to lead" (see duke (n.)). Sexual sense, now the prevailing one, is attested from 1550s and apparently was not in Latin. Originally "entice (a woman) to a surrender of chastity." Related: Seduced; seducing.

Replaced Middle English seduisen (late 15c.), from Middle French séduire "seduce," from Old French suduire "to corrupt, seduce," from Latin subducere "draw away, withdraw, remove" (see subduce).
seductible (adj.)
1620s, from seduct-, past participle stem of Latin seducere (see seduce) + -ible. Related: Seductibly; seductibility.
seduction (n.)
1520s, from Middle French séduction, from Latin seductionem (nominative seductio), noun of action from past participle stem of seducere (see seduce). Originally with reference to actions or beliefs; sexual sense is from 1769, originally always with women as the objects. Earlier appearance of the word in Middle English with a sense "treason, treachery" probably is a confusion with sedition, which confusion also is found in Old French seducion "treason, betrayal."
seductive (adj.)
1740, from Latin seduct-, past participle stem of seducere (see seduce) + -ive. Related: Seductively; seductiveness. Middle English had seducious "deceitful, devious" (mid-15c.).
seductress (n.)
1803, "female seducer," with -ess + obsolete seductor (late 15c., displaced by seducer), from a direct borrowing of the Latin agent noun of seducere (see seduce).
sedulity (n.)
1540s, from Latin sedulitas "assiduity, application," noun of quality from sedulus (see sedulous).
sedulous (adj.)
1530s, from Latin sedulus "attentive, painstaking, diligent, busy, zealous," probably from sedulo (adv.) "sincerely, diligently," from sedolo "without deception or guile," from se- "without, apart" (see secret) + dolo, ablative of dolus "deception, guile," cognate with Greek dolos "ruse, snare." Related: Sedulously; sedulousness.
sedum (n.)
mid-15c., from Latin sedum "houseleek."
see (v.)
Old English seon "to see, look, behold; observe, perceive, understand; experience, visit, inspect" (contracted class V strong verb; past tense seah, past participle sewen), from Proto-Germanic *sekhwan (cognates: Old Saxon, Old High German sehan, Middle High German, German sehen, Old Frisian sia, Middle Dutch sien, Old Norse sja, Gothic saihwan), from PIE root *sekw- (2) "to see," which is probably identical with *sekw- (1) "to follow" (see sequel), a root which produced words for "say" in Greek and Latin, and also words for "follow" (such as Latin sequor), but "opinions differ in regard to the semantic starting-point and sequences" [Buck]. Thus see might originally mean "follow with the eyes."

Used in Middle English to mean "behold in the imagination or in a dream" (c.1200), "to recognize the force of (a demonstration)," also c.1200. Sense of "escort" (as in to see (someone) home) first recorded 1607 in Shakespeare. Meaning "to receive as a visitor" is attested from c.1500. Gambling sense of "equal a bet" is from 1590s. See you as a casual farewell first attested 1891. Let me see as a pausing statement is recorded from 1510s. To have seen everything as a hyperbolic expression of astonishment is from 1957.
When you have seen one of their Pictures, you have seen all. [Blake, c.1811]
see (n.)
c.1300, "throne of a bishop, archbishop, or pope," also "throne of a monarch, a goddess, Antichrist, etc.," from Old French sie "seat, throne; town, capital; episcopal see," from Latin sedem (nominative sedes) "seat, throne, abode, temple," related to sedere "to sit" (see sedentary). Early 14c. as "administrative center of a bishopric;" c.1400 as "province under the jurisdiction of a bishop."
see-saw (n.)
also seesaw, 1630s, in see-saw-sacke a downe (like a Sawyer), words in a rhythmic jingle used by children and repetitive motion workers, probably imitative of the rhythmic back-and-forth motion of sawyers working a two-man saw over wood or stone (see saw. Ha ha.). Reference to a game of going up and down on a balanced plank is recorded from 1704; figurative sense is from 1714. Applied from 1824 to the plank arranged for the game.
see-saw (v.)
also seesaw, "move up and down," 1712, from see-saw (n.). Related: See-sawed; see-sawing.
see-through (adj.)
1950, from the verbal phrase (c.1400); see see (v.) + through (adv.).
seed (v.)
late 14c., "to flower, flourish; produce seed;" mid-15c., "to sow with seed," from seed (n.). Meaning "remove the seeds from" is from 1904. Sporting (originally tennis) sense (1898) is from notion of spreading certain players' names so as to ensure they will not meet early in a tournament. The noun in this sense is attested from 1924. Related: Seeded; seeding.
seed (n.)
Old English sed, sæd "that which may be sown; an individual grain of seed; offspring, posterity," from Proto-Germanic *sediz "seed" (cognates: Old Norse sað, Old Saxon sad, Old Frisian sed, Middle Dutch saet, Old High German sat, German Saat), from PIE *se-ti- "sowing," from root *se- (1) "to sow" (see sow (v.)). Figurative use in Old English. Meaning "offspring, progeny" rare now except in biblical use. Meaning "semen" is from c.1300. For sporting sense, see seed (v.).
seed-cake (n.)
1570s, from seed (n.) + cake (n.).
seeded (adj.)
1922 in the sports sense (originally tennis), past participle adjective from seed (v.).
seedling (n.)
"young plant developed from seed," 1650s, from seed (n.) + diminutive suffix -ling.