1540s, "quality of being real, objective reality," from French réalité and directly from Medieval Latin realitatem (nominative realitas), from Late Latin realis (see real (adj.)). Also compare realty, which was the older form of the word in the sense of "reality" (mid-15c.).
Meaning "real existence, what is real, the aggregate of all that is real" is from 1640s; that of "the real state (of something)" is from 1680s. Sometimes 17c.-18c. it also meant "sincerity." Reality-based is attested from 1960, in marriage counseling. Reality television is attested from 1991.
General sense of "combination for a common object" is from mid-14c., as are those of "bond or treaty between rulers or nations, contracted by treaty" and "aggregate of persons allied." Unlike its synonyms, "rarely used of a combination for evil" [Century Dictionary]. Meaning "state of being allied or connected" is from 1670s. The Latin word was alligantia.
"a collection into one mass or aggregate," 1610s, from Latin congeries "heap, pile, collected mass," from congerere "to bring together, pile up," from assimilated form of com "with, together" (see con-) + gerere "to carry, perform" (see gest). False singular congery is attested by 1866.
Man should have some sense of responsibility to the human congeries. As a matter of observation, very few men have any such sense. No social order can exist very long unless a few, at least a few, men have such a sense. [Ezra Pound, "ABC of Economics," 1933]
c. 1300, "body part or organ, an integral part of an animal body having a distinct function" (in plural, "the body"), from Old French membre "part, portion; topic, subject; limb, member of the body; member" (of a group, etc.)," 11c., from Latin membrum "limb, member of the body, part," probably from PIE *mems-ro, from root *mems- "flesh, meat" (source also of Sanskrit mamsam "flesh;" Greek meninx "membrane," mēros "thigh" (the "fleshy part"); Gothic mimz "flesh").
In common use, "one of the limbs or extremities." Especially "the sex organ" (c. 1300, compare Latin membrum virile, but in English originally of women as well as men). Figurative sense of "anything likened to a part of the body" is by 14c., hence "a component part of any aggregate or whole, constituent part of a complex structure, one of a number of associated parts or entities."
The transferred sense of "person belonging to a group" is attested from mid-14c., from notion of "person considered in relation to an aggregate of individuals to which he or she belongs," especially one who has united with or been formally chosen as a corporate part of an association or public body. This meaning was reinforced by, if not directly from, the use of member in Christian theology and discourse from mid-14c. for "a Christian" (a "member" of the Church as the "Body of Christ"). Meaning "one who has been elected to parliament" is from early 15c.
c. 1300, "institution of higher learning," also "body of persons constituting a university," from Anglo-French université, Old French universite "universality; academic community" (13c.), from Medieval Latin universitatem (nominative universitas), "the whole, aggregate," in Late Latin "corporation, society," from universus "whole, entire" (see universe). In the academic sense, a shortening of universitas magistrorum et scholarium "community of masters and scholars;" superseded studium as the word for this. The Latin word also is the source of Spanish universidad, German universität, Russian universitet, etc.
Meaning "act or process of making a mark upon the surface by pressing" is from early 15c.. Meaning "copy made by pressure from type or an engraving" is from 1550s; that of "printing of a number of copies, aggregate of copies printed at one time" is from 1570s. Meaning "belief, vague notion" (as in under the impression) is from 1610s.
"each, considered indefinitely as a unitary part of an aggregate; all, of a collective or aggregate number, taken one by one;" early 13c., contraction of Old English æfre ælc "each of a group," literally "ever each" (Chaucer's everich), from each with ever added before it for emphasis. The word still is felt to want emphasis; as in Modern English every last ..., every single ..., etc.
Also a pronoun to Chaucer, Shakespeare, Spenser, "each of any number of persons or things; every one." Compare everybody, everything, etc. The word everywhen is attested from 1843 but never caught on; neither did everyhow (1837).
Every now and then "repeatedly, at short intervals" is from 1660s. Every once in a while, U.S. colloquial, "now and then, from time to time," is attested from 1814 (Bartlett calls it "A singular though very common expression"). Slang phrase every Tom, Dick, and Harry "every man, everyone" dates from at least 1723, from the common English given names.
That is to ſay, they affirm, that once upon a Time (tho' they never yet could tell when) all Mankind were upon a Level, and that there was no ſuch Thing as Government in the World; and that Tom, Dick, and Harry, ay, every individual Man, Woman, and Child, had a Right to the whole World. [Charles Leslie, "A Short and Eaſie Method with the Deists," London, 1723]
1630s, "the 1,000-year period of Christ's anticipated rule on Earth" (Revelation xx.1-5); from Modern Latin millennium, from Latin mille "thousand" (see million) + annus "year" (see annual); formed on analogy of biennium, triennium, etc. For vowel change, see biennial. General (non-theological) sense of "an aggregate of 1,000 years, a period or interval of 1,000 years" is attested by 1711. Meaning "the year 2000 A.D." is attested by 1970.
[T]he men of the modern world—up to a generation ago anyway—saw 2000 as a millennial year in the light of science. Men were then to be freed of want, misery, and disease; reason and advanced technology would rule; all would finally be for the best in what would then be the undoubted best of all possible worlds. [Bulletin of the Atomic Scientists, December 1962]
In the Biblical sense, which was the original one in English, the Latin word translates Greek phyle "race or tribe of men, body of men united by ties of blood and descent, a clan" (see phylo-). Extension to modern ethnic groups or races of people is from 1590s, specifically "a division of a barbarous race of people, usually distinguishable in some way from their congeners, united into a community under a recognized head or chief" [Century Dictionary], but colloquially of any aggregate of individuals of a kind.