ballyoudaoicibaDictYouDict[ball 词源字典]
ball: There are two distinct words ball in English. The ‘round object’ [13] comes via Old Norse böllr from a prehistoric Germanic *balluz (source also of bollock [OE], originally a diminutive form). A related form was Germanic *ballōn, which was borrowed into Italian to give palla ‘ball’, from which French probably acquired balle.

Derivatives of this branch of the family to have reached English are balloon [16], from French ballon or Italian ballone, and ballot [16], from the Italian diminutive form ballotta (originally from the use of small balls as counters in secret voting). The Germanic stem form *bal-, *bul- was also the ultimate source of English bowl ‘receptacle’.

The ‘dancing’ ball [17] comes from French bal, a derivative of the now obsolete verb bal(l)er ‘dance’, which was descended via late Latin ballāre from Greek ballízein ‘dance’. Related words in English include ballad(e) [14], which came via Old French from Provençal balada ‘song or poem to dance to’, and ballet.
=> ballon, ballot, bollock; ballad, ballet[ball etymology, ball origin, 英语词源]
ball (n.1)youdaoicibaDictYouDict
"round object," Old English *beal, from or corresponding to Old Norse bollr "ball," from Proto-Germanic *balluz (cognates: Old High German ballo, German Ball), from PIE root *bhel- (2) "to blow, inflate, swell" (see bole).

Meaning "testicle" is from early 14c. Ball of the foot is from mid-14c. A ball as an object in a sports game is recorded from c. 1200; To have the ball "hold the advantage" is from c. 1400. To be on the ball is 1912, from sports. Ball-point pen first recorded 1946. Ball of fire when first recorded in 1821 referred to "a glass of brandy;" as "spectacularly successful striver" it is c. 1900.
ball (n.2)youdaoicibaDictYouDict
"dancing party," 1630s, from French, from Old French baller "to dance," from Late Latin ballare "to dance," from Greek ballizein "to dance, jump about" (see ballistics). Hence, "very enjoyable time," 1945, American English slang, perhaps back to 1930s in black slang.
ball (v.)youdaoicibaDictYouDict
1650s, "make into a ball," from ball (n.1). Sense of "to become like a ball" is 1713; that of "to copulate" is first recorded 1940s in jazz slang, either from the noun sense of "testicle" or "enjoyable time" (from ball (n.2)). Related: Balled; balling.