c. 1300, "a quick, light blow, stroke," also "a fart" (late 15c.), native or borrowed from a Scandinavian source (compare Danish rap, Swedish rapp "light blow"); either way probably of imitative origin (compare slap, clap).
Slang meaning "rebuke, blame, responsibility" is from 1777; specific meaning "criminal indictment" (as in rap sheet, 1960) is from 1903. To beat the rap is from 1927. Meaning "music with improvised words" first in New York City slang, 1979 (see rap (v.2)).
rap (v.1)
mid-14c., "strike, smite, knock," from rap (n.). Related: Rapped; rapping. To rap (someone's) knuckles "give light punishment" is from 1749. Related: Rapped; rapping.
rap (v.2)
"talk informally, chat," 1929, popularized c. 1965 in Black English, possibly first in Caribbean English and from British slang meaning "say, utter" (1879), originally "to utter a sudden oath" (1540s), ultimately from rap (n.). As a noun in this sense from 1898. Meaning "to perform rap music" is recorded by 1979. Related: Rapped; rapping.
例文
1. He said statisticians gave them a bad rap by "lying with figures ".
統計学者は「データで嘘をつく」と言って、彼らの名声を傷つけた。The rap on this guy is that he doesn 't really care.
こいつはあまり気にしていないそうだ。
3.Britain gave them a diplomatic rap over the knuckles.
イギリスは彼らを外交的に非難した。
4.We rap the manufactures on their knuckles if the toy is shoddy.
おもちゃの品質が悪いと、メーカーを痛烈に非難します。
5.The rap against Conn was that he was far too reckless.