agogyoudaoicibaDictYouDict[agog 词源字典]
agog: [15] Agog probably comes from Old French gogue ‘merriment’. It was used in the phrase en gogue, meaning ‘enjoying oneself’ (Randle Cotgrave, in his Dictionarie of the French and English tongues 1611, defines estre en ses gogues as ‘to be frolicke, lustie, lively, wanton, gamesome, all-a-hoit, in a pleasant humour; in a veine of mirth, or in a merrie mood’), and this was rendered into English as agog, with the substitution of the prefix a- (as in asleep) for en and the meaning toned down a bit to ‘eager’.

It is not clear where gogue came from (it may perhaps be imitative of noisy merrymaking), but later in its career it seems to have metamorphosed into go-go, either through reduplication of its first syllable (gogue had two syllables) or through assimilation of the second syllable to the first: hence the French phrase à go-go ‘joyfully’, and hence too English go-go dancers.

[agog etymology, agog origin, 英语词源]
blow (n.1)youdaoicibaDictYouDict
"hard hit," mid-15c., blowe, from northern and East Midlands dialects, perhaps from Middle Dutch blouwen "to beat," a common Germanic word of unknown origin (compare German bleuen, Gothic bliggwan "to strike"). Influenced in English by blow (v.1). In reference to descriptions or accounts, blow-by-blow is recorded from 1921, American English, originally of prize-fight broadcasts.
LIKE a hungry kitten loves its saucer of warm milk, so do radio fans joyfully listen to the blow-by-blow broadcast description of a boxing bout. ["The Wireless Age," December 1922]
fiddle (n.)youdaoicibaDictYouDict
"stringed musical instrument, violin," late 14c., fedele, fydyll, fidel, earlier fithele, from Old English fiðele "fiddle," which is related to Old Norse fiðla, Middle Dutch vedele, Dutch vedel, Old High German fidula, German Fiedel "a fiddle;" all of uncertain origin.

The usual suggestion, based on resemblance in sound and sense, is that it is from Medieval Latin vitula "stringed instrument" (source of Old French viole, Italian viola), which perhaps is related to Latin vitularia "celebrate joyfully," from Vitula, Roman goddess of joy and victory, who probably, like her name, originated among the Sabines [Klein, Barnhart]. Unless the Medieval Latin word is from the Germanic ones.
FIDDLE, n. An instrument to tickle human ears by friction of a horse's tail on the entrails of a cat. [Ambrose Bierce, "The Cynic's Word Book," 1906]
Fiddle has been relegated to colloquial usage by its more proper cousin, violin, a process encouraged by phraseology such as fiddlesticks (1620s), contemptuous nonsense word fiddle-de-dee (1784), and fiddle-faddle. Century Dictionary reports that fiddle "in popular use carries with it a suggestion of contempt and ridicule." Fit as a fiddle is from 1610s.
gamely (adv.)youdaoicibaDictYouDict
"courageously," 1861, from game (adj.2) + -ly (2). In Old English and Middle English the adverb meant "artfully; joyfully."
gaudy (adj.)youdaoicibaDictYouDict
"showy, tastelessly rich," c. 1600; earlier "joyfully festive" (1580s), probably a re-adjectivizing of gaudy (n.) "large, ornamental bead in a rosary" (early 14c.) via the noun gaud + -y (2.). In early Modern English it also could mean "full of trickery" (1520s).

Or possibly the adjective is from or influenced by Middle English noun gaudegrene (early 14c.), name of a yellowish-green color or pigment, originally of dye obtained from the weld plant (see weld (n.1)). This Germanic plant-name became gaude in Old French, and thus the Middle English word. Under this theory, the sense shifted from "weld-dye" to "bright ornamentation."

As a noun, "feast, festival" 1650s, from gaudy day "day of rejoicing" (1560s).
gladly (adv.)youdaoicibaDictYouDict
Old English glædlice "joyfully, kindly, willingly" (also "bright, shining; pleasant, agreeable"); see glad (adj.) + -ly (2).
joyful (adj.)youdaoicibaDictYouDict
mid-13c., from joy + -ful. Related: Joyfully; joyfulness.