c. 1200, "lacking money or resources, destitute of wealth; needy, indigent;" also "small, scanty," also voluntarily and deliberately, "devoid of possessions in conformity with Christian virtues," from Old French povre "poor, wretched, dispossessed; inadequate; weak, thin" (Modern French pauvre), from Latin pauper "poor, not wealthy," from pre-Latin *pau-paros "producing little; getting little," a compound from the roots of paucus "little" (from PIE root *pau- (1) "few, little") and parare "to produce, bring forth" (from PIE root *pere- (1) "to produce, procure").
It replaced Old English earm (from Proto-Germanic *arma-, which is of disputed origin). Late 13c. as "unfortunate, to be pitied or regretted." In contemptuous use, "morally inferior, miserable, wretched," by early 15c. Used figuratively ("spiritually poor") from early 14c. (to be poor in spirit is to be "spiritually humble"). Meaning "deficient in desirable or essential qualities" is from c. 1300. In reference to inhabited places from c. 1300; of soil, etc., from late 14c. In modest or apologetic use, "humble, slight, insignificant," from early 15c.
The poor boy sandwich, made of simple but filling ingredients, was invented and named in New Orleans in 1921. To poor mouth "deny one's advantages" is from 1965 (to make a poor mouth "whine" is Scottish dialect from 1822). Slang poor man's________ "the cheaper alternative to _______," is from 1854. Poor relation "relative or kinsman in humble circumstances" is by 1720.
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.
"poor persons collectively," mid-12c., from poor (adj.). The Latin adjective pauper "poor" also was used in a noun sense "a poor man." Middle English used poorlet (late 14c.) "poor man, wretched person" to translate Latin paupercula in the Bible.
"reckless, careless," 1828 (but suggested in other forms by 1793). As an oath or expression by 1815.