"ignorant, dull," 1590s, from Boeotia, the district around Thebes in ancient Greece (said to have been so called for its cattle pastures; from Greek bous "ox," from PIE root *gwou- "ox, bull, cow"), whose inhabitants were characterized as proverbially dull and countrified by their neighbors the Athenians, who thought Boeotia "a canton hopelessly behind the times, a slow canton, as the nimble Attics would say, a glorious climate for eels, but a bad air for brains" [B.L. Gildersleeve, "Pindar: The Olympian and Pythian Odes"]. The Boeotians presumably held reciprocal opinions, but their great writers, Plutarch and Pindar, though patriots, are full of praise for Athenian deeds and institutions.

Though his aim was to vindicate Boeotia, [Pindar] has probably done her a disservice, in that he has helped to immortalise the scurrilous proverb Βοιωτία ύς [Boeotian swine], which he wished to confute. ... If left to itself, the slander might have passed into oblivion long ago. [W. Rhys Roberts, "The Ancient Boeotians," 1895]

1590s, "bewitch, enchant," from French fasciner (14c.), from Latin fascinatus, past participle of fascinare "bewitch, enchant, fascinate," from fascinus "a charm, enchantment, spell, witchcraft," which is of uncertain origin. Earliest used of witches and of serpents, who were said to be able to cast a spell by a look that rendered one unable to move or resist. Sense of "delight, attract and hold the attention of" is first recorded 1815.

To fascinate is to bring under a spell, as by the power of the eye; to enchant and to charm are to bring under a spell by some more subtle and mysterious power. This difference in the literal affects also the figurative senses. [Century Dictionary]

Possibly from Greek baskanos "slander, envy, malice," later "witchcraft, sorcerery," with form influenced by Latin fari "speak" (see fame (n.)), but others say the resemblance of the Latin and Greek words is accidental. The Greek word might be from a Thracian equivalent of Greek phaskein "to say;" compare enchant, and German besprechen "to charm," from sprechen "to speak." Watkins suggests the Latin word is perhaps from PIE *bhasko- "band, bundle" via a connecting sense of "amulet in the form of a phallus" (compare Latin fascinum "human penis; artificial phallus; dildo"). Related: Fascinated; fascinating.

If [baskanos] and fascinum are indeed related, they would point to a meaning 'curse, spell' in a loanword from an unknown third language. [de Vaan]

"impious or profane speaking of God or sacred things," early 13c., from Old French blasfemie "blasphemy," from Late Latin blasphemia, from Greek blasphēmia "a speaking ill, impious speech, slander," from blasphēmein "to speak evil of."

The second element of that is phēmē "utterance" (from PIE root *bha- (2) "to speak, tell, say"); the first element is uncertain, perhaps it is related to blaptikos "hurtful," though blax "slack (in body and mind), stupid" also has been proposed; de Vaan suggests a connection with the root of Latin malus "bad, unpleasant" (from PIE root *mel- (3)). In Old Testament usage, the word applied to a more specific crime, against the reverence for Jehovah as ruler of the Jews, comparable to treason.

Blasphemy cognizable by common law is described by Blackstone to be "denying the being or providence of God, contumelious reproaches of our Saviour Christ, profane scoffing at the Holy Scripture, or exposing it to contempt or ridicule"; by Kent as "maliciously reviling God or religion"; and by Chief Justice Lemuel Shaw as "speaking evil of the Deity with an impious purpose to derogate from the Divine Majesty and to alienate the minds of others from the love and reverence of God." [Century Dictionary, 1895]

To laugh at the pretensions of Mohammed in Constantinople is blasphemy. To say in St Petersburg that Mohammed was a prophet of God is also blasphemy. There was a time when to acknowledge the divinity of Christ in Jerusalem was blasphemy. To deny his divinity is now blasphemy in New York. Blasphemy is to a considerable extent a geographical question. [Robert G. Ingersoll, quoted in "Discussions," 1902]

Old English deofol "a devil, a subordinate evil spirit afflicting humans;" also, in Christian theology, "the Devil, a powerful spirit of evil otherwise known as Satan," from Late Latin diabolus (also the source of Italian diavolo, French diable, Spanish diablo; German Teufel is Old High German tiufal, from Latin via Gothic diabaulus).

The Late Latin word is from Ecclesiastical Greek diabolos, which in Jewish and Christian use was "the Devil, Satan," and which in general use meant "accuser, slanderer" (thus it was a scriptural loan-translation of Hebrew satan; see Satan). It is an agent noun from Greek diaballein "to slander, attack," literally "to throw across," from dia "across, through" (see dia-) + ballein "to throw" (from PIE root *gwele- "to throw, reach").

Jerome re-introduced Satan in Latin bibles, and English translators have used both words in different measures. In Vulgate, as in Greek, diabolus and dæmon (see demon) were distinct, but they have merged in English and other Germanic languages.

Meaning "false god, heathen god" is from c. 1200. Sense of "diabolical person, person resembling a devil or demon in character" is from late 12c. Playful use for "clever rogue" is from c. 1600. As an expletive and in expletive phrases from c. 1200.

Meaning "sand spout, dust storm" is from 1835 (dust devil is attested by 1867). In U.S. place names, the word often represents a native word such as Algonquian manito, more properly "spirit, god." Phrase a devil way (c. 1300) was originally "Hell-ward, to Hell," but by late 14c. it was a mere expression of irritation. Meaning "errand-boy in a printing office" is from 1680s, perhaps because they were often blackened by the ink (devils then being popularly supposed to be black).

Devil's books "playing cards" is from 1729, but the cited quote says they've been called that "time out of mind" (the four of clubs is the devil's bedposts); devil's coach-horse is from 1840, the large rove-beetle, which is defiant when disturbed. Devil's food cake (1895; three different recipes in the cookbook "compiled by the Ladies' Aid Society of the Friends' Church, Wilmington, Ohio"), rich and chocolate, probably is in deliberate contrast to angel food cake. Conventional phrase talk (or speak)of the Devil, and he's presently at your elbow is by 1660s.