1550s, "harmonious;" 1570s, "sticking together," also "connected, consistent" (of speech, thought, etc.), from French cohérent (16c.), from Latin cohaerentem (nominative cohaerens), present participle of cohaerere "cohere," from assimilated form of com "together" (see co-) + haerere "to adhere, stick" (see hesitation).
"of or causing the quality of adhering together; capable of sticking," 1730, with -ive + Latin cohaes-, past participle stem of cohaerere "to cleave together," in transferred use, "be coherent or consistent," from assimilated form of com "together" (see co-) + haerere "to adhere, stick" (see hesitation). Related: Cohesively; cohesiveness.
1590s, "to be consistent, to follow regularly in natural or logical order," from Latin cohaerere "to cleave together," in transferred use, "be coherent or consistent," from assimilated form of com "together" (see co-) + haerere "to adhere, stick" (see hesitation). More literal sense of "to stick, stick together, cleave" is from 1610s. Related: Cohered; cohering.
1580s, "suitable connection or dependence, consistency" (in narrative or argument), also more literally "act or state of sticking or cleaving of one thing to another," from French cohérence (16c.), from Latin cohaerentia, abstract noun from cohaerentem(nominative cohaerens), present participle of cohaerere "to stick together, be coherent," from assimilated form of com "together" (see co-) + haerere "to adhere, stick" (see hesitation). Related: Coherency.
1830, from French mythe (1818) and directly from Modern Latin mythus, from Greek mythos "speech, thought, word, discourse, conversation; story, saga, tale, myth, anything delivered by word of mouth," a word of unknown origin. Beekes finds it "quite possibly Pre-Greek."
Myths are "stories about divine beings, generally arranged in a coherent system; they are revered as true and sacred; they are endorsed by rulers and priests; and closely linked to religion. Once this link is broken, and the actors in the story are not regarded as gods but as human heroes, giants or fairies, it is no longer a myth but a folktale. Where the central actor is divine but the story is trivial ... the result is religious legend, not myth." [J. Simpson & S. Roud, "Dictionary of English Folklore," Oxford, 2000, p.254]
General sense of "untrue story, rumor, imaginary or fictitious object or individual" is from 1840.
late 14c., "irregular shaped lump; body of unshaped, coherent matter," from Old French masse "lump, heap, pile; crowd, large amount; ingot, bar" (11c.), and directly from Latin massa "kneaded dough, lump, that which adheres together like dough," probably from Greek maza "barley cake, lump, mass, ball," which is related to massein "to knead," from PIE root *mag- "to knead, fashion, fit."
The sense in English was extended 1580s to "a large quantity, amount, or number." Meaning "bulk" in general is from c. 1600. As "the bulk or greater part of anything" from 1620s. Strict sense in physics, "quantity of a portion of matter expressed in pounds or grams" is from 1704.
As an adjective, "of, involving, or composed of masses of people; done on a large scale," from 1733, first attested in American English mass meeting "public assembly persons in mass or of all classes to consider or listen to the discussion of some matter of common interest." Mass culture is from 1916 in sociology (earlier in biology); mass hysteria is from 1914; mass movement is from 1897; mass grave is from 1918; mass murder from 1880.