"a stick or staff used in beating, a war-club, staff used to strike the ball in certain games," c. 1200, from rare Old English batt "cudgel," a western England word at first, probably from Welsh or another Celtic source (compare Irish and Gaelic bat, bata "staff, cudgel"), later reinforced and influenced by Old French batte "pestle," from Late Latin battre "to beat;" all from PIE root *bhat- "to strike." As a kind of wooden paddle used to play cricket (later baseball), it is attested from 1706.
Middle English sense of "a lump, piece, chunk" (mid-14c.) was used of bread, clay, wool, and survives in brickbat and batting (n.1). Phrase right off the bat (1866), also hot from the bat (1870), probably represent a baseball metaphor, but cricket or some other use of a bat might as easily be the source--there is an early citation from Australia (in an article about slang): "Well, it is a vice you'd better get rid of then. Refined conversation is a mark of culture. Let me hear that kid use slang again, and I'll give it to him right off the bat. I'll wipe up the floor with him. I'll ---" ["The Australian Journal," November 1888].
Old English fretan "devour, feed upon, consume," from Proto-Germanic compound *fra-etan "to eat up," from *fra- "completely" (from PIE root *per- (1) "forward," hence "through") + *etan "to eat" (from PIE root *ed- "to eat"). Cognates include Dutch vreten, Old High German frezzan, German fressen, Gothic fraitan.
Used of monsters and Vikings; in Middle English used of animals' eating. Notion of "wear away by rubbing or scraping" (c. 1200) might have come to this word by sound-association with Anglo-French forms of Old French froter "to rub, wipe; beat, thrash," which is from Latin fricare "to rub" (see friction). Figurative use is from c. 1200, of emotions, sins, vices, etc., "to worry, consume, vex" someone or someone's heart or mind, from either the "eating" or the "rubbing" sense. Intransitive sense "be worried, vex oneself" is by 1550s. Modern German still distinguishes essen for humans and fressen for animals. Related: Fretted; fretting. As a noun, early 15c., "a gnawing," also "the wearing effect" of awareness of wrongdoing, fear, etc.
"pertaining to atoms," 1670s as a philosophical term (see atomistic); scientific sense dates from 1811, from atom + -ic. Atomic number is from 1821; atomic mass is from 1848. Atomic energy first recorded 1906 in modern sense (as intra-atomic energy from 1903).
March, 1903, was an historic date for chemistry. It is, also, as we shall show, a date to which, in all probability, the men of the future will often refer as the veritable beginning of the larger powers and energies that they will control. It was in March, 1903, that Curie and Laborde announced the heat-emitting power of radium. [Robert Kennedy Duncan, "The New Knowledge," 1906]
Atomic bomb first recorded 1914 in writings of H.G. Wells ("The World Set Free"), who thought of it as a bomb "that would continue to explode indefinitely."
When you can drop just one atomic bomb and wipe out Paris or Berlin, war will have become monstrous and impossible. [S. Strunsky, Yale Review, January 1917]
Atomic Age is from 1945. Atomical "concerned with atoms," also "very minute," is from 1640s. Atomic clock is from 1938.
"opaque white fluid secreted by mammary glands of female mammals, suited to the nourishment of their young," Middle English milk, from Old English meoluc (West Saxon), milc (Anglian), from Proto-Germanic *meluk- "milk" (source also of Old Norse mjolk, Old Frisian melok, Old Saxon miluk, Dutch melk, Old High German miluh, German Milch, Gothic miluks), from *melk- "to milk," from PIE root *melg- "to wipe, to rub off," also "to stroke; to milk," in reference to the hand motion involved in milking an animal. Old Church Slavonic noun meleko (Russian moloko, Czech mleko) is considered to be adopted from Germanic.
Of milk-like plant juices or saps from c. 1200. Milk chocolate (eating chocolate made with milk solids, paler and sweeter) is recorded by 1723; milk shake was used from 1889 for a variety of concoctions, but the modern version (composed of milk, flavoring, etc., mixed by shaking) is from the 1930s. Milk tooth (1727) uses the word in its figurative sense "period of infancy," attested from 17c. To cry over spilt milk (representing anything which, once misused, cannot be recovered) is first attested 1836 in writing of Canadian humorist Thomas C. Haliburton. Milk and honey is from the Old Testament phrase describing the richness of the Promised Land (Numbers xvi.13, Old English meolc and hunie). Milk of human kindness is from "Macbeth" (1605).