古英語のbetst.betから、bootと同じ、恩恵。-bootという単語は死語に近く、善の最上級である。
The best-laid schemes o' mice an' menBest-seller as short for "best-selling book" is from 1902, apparently originally in the publishing trade; best friend was in Chaucer (late 14c.). Best girl is first attested 1881, American English; best man is 1814, originally Scottish, replacing groomsman. To be able to do something with the best of them is recorded by 1748.
Gang aft agley,
An' lea'e us nought but grief an' pain,
For promis'd joy!
[Burns]