"A new manufactory of a nectar, between soda-water and ginger-beer, and called pop, because ‘pop goes the cork’ when it is drawn." [Southey, letter, 1812]Baseball sense of "to hit a ball high in the air" is from 1867. Sense of "ice cream on a stick" is from 1923 (see popsicle). To pop the question is from 1725, specific sense of "propose marriage" is from 1826. Popcorn is first attested 1819. Pop-eyed "having bulging eyes" is recorded from 1820. Pop-gun as a type of child's toy is from 1622. Pop-over "light cake" is from 1876. Pop goes the weasel, a country dance, was popular 1850s at court balls, etc.
"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]
Pornographer is earliest form of the word, attested from 1850. Pornocracy (1860) is "the dominating influence of harlots," used specifically of the government of Rome during the first half of the 10th century by Theodora and her daughters.