1704, "kernel of a nut;" 1708, "head of a comet;" from Latin nucleus "kernel," from nucula "little nut," diminutive of nux (genitive nucis) "nut," from PIE *kneu- "nut" (source also of Middle Irish cnu, Welsh cneuen, Middle Breton knoen "nut," Old Norse hnot, Old English hnutu "nut").
The general sense of "central mass or thing, about which others cluster or matter collects," is from 1762. In biology, "dense, typically rounded structure in a cell, bounded by membranes," from 1831. Later they were found to contain the genetic material. Modern meaning in physics, "positively charged central core of an atom," is from 1912, by Ernest Rutherford, though theoretical use for "central point of an atom" is from 1844, in Faraday.
c. 1200, piler, "a column or columnar mass, narrow in proportion to height, either weight-bearing or free-standing," from Old French piler "pillar, column, pier" (12c., Modern French pilier) and directly from Medieval Latin pilare, from Latin pila "pillar, stone barrier," a word of unknown etymology. The figurative sense of "prop or support of an institution or community" is recorded from early 14c. Related: Pillared.
In medieval architecture often made so as to give the appearance of several shafts around a central core; "by architects often distinguished from column, inasmuch as it may be of any shape in section, and is not subordinated to the rules of classic architecture" [Century Dictionary].
Phrase pillar to post "from one thing to another without apparent or definite purpose" is attested from c. 1600, late 15c. as post to pillar, mid-15c. as pillar and post; but the exact meaning is obscure. Earliest references seem to allude to tennis, but post and pillar is recorded as the name of a game of some sort c. 1450. The theory that the expression is from pillar as the raised ground at the center of a manège ring around which a horse turns is unlikely because that sense seem to date only to 18c.
The Pillars of Hercules are the two hills on opposite sides of the Straits of Gibraltar, Abyla in Africa and Calpe in Europe, said to have been torn asunder by Hercules.
From c. 1200 of material things, "not stiff, not coarse, fine; yielding to weight." From late 14c. of wind, rain, etc. Of sounds, "quiet, not loud," from early 13c. Of words, "mild, restrained; courteous" mid-14c. From late 14c. as "indulgent," also "physically feeble; easily overcome, lacking manly courage." From 1755 of water ("relatively free from mineral salts"), from 1789 of coal. Meaning "foolish, simple, silly" is attested from 1620s; earlier "easily moved or swayed; soft-hearted, sympathetic; docile" (early 13c.). In reference to drinks, "non-alcoholic" from 1880. As an adverb, Old English softe "gently;" late 13c. as "quietly." As an interjection from 1540s.
Soft landing is from 1958 and the U.S. space program. Adjective soft-core (in reference to pornography) is from 1966 (see hardcore). Soft rock as a music style is attested from 1969. Soft sell is from 1955. Soft-shoe as a dancing style is attested from 1927. Soft-boiled is from 1757 of eggs; of persons, ideas, etc., 1930 (compare half-baked). Soft-focus (adj.) of camera shots is from 1917. The softer sex "women collectively" is from 1640s.
1842, "ancient obscene painting, especially in temples of Bacchus," from French pornographie, from Greek pornographos "(one) depicting prostitutes," from graphein "to write" (see -graphy) + pornē "prostitute," originally "bought, purchased" (with an original notion, probably of "female slave sold for prostitution"), related to pernanai "to sell" (from PIE *perə-, variant of root *per- (5) "to traffic in, to sell").
A brothel in ancient Greek was a porneion. In reference to modern works by 1859 (originally French novels), later as a charge against native literature; the sense of "obscene pictures" in modern times is from 1906. Also sometimes used late 19c. for "description of prostitutes" as a matter of public hygiene.
Pornography, or obscene painting, which in the time of the Romans was practiced with the grossest license, prevailed especially at no particular period in Greece, but was apparently tolerated to a considerable extent at all times. Parrhasius, Aristides, Pausanias, Nicophanes, Chaerephanes, Arellius, and a few other [pornographoi] are mentioned as having made themselves notorious for this species of license. [Charles Anthon, "Dictionary of Greek and Roman Antiquities," New York, 1843]
I shall not today attempt further to define the kinds of material I understand to be embraced within that shorthand description [hard-core pornography]; and perhaps I could never succeed in intelligibly doing so. But I know it when I see it, and the motion picture involved in this case is not that. [U.S. Supreme Court Justice Potter Stewart, concurring opinion, "Jacobellis v. Ohio," 1964]
E. Bray in The Medical Archives [December 1872] proposed porniatria for "the lengthy and really meaningless expression 'social evil hospital' ...." In ancient contexts, often paired with rhypography, "genre painting of low, sordid, or unsuitable subjects."
Pornocracy (1860) is "the dominating influence of harlots," used specifically of the control of the government of Rome and the election to the Papacy during the first half of the 10th century by the noble but profligate Theodora and her daughters. Pornotopia (1966) was coined to describe the ideal erotic-world of pornographic movies.