dashing (adj.)youdaoicibaDictYouDict[dashing 词源字典]
1801, "given to cutting a dash" (1786), which was a colloquial expression for "acting brilliantly," from dash (n.) in the sense of "showy appearance," which is attested from 1715. The sense of "splashing" is recorded from mid-15c.[dashing etymology, dashing origin, 英语词源]