coarseyoudaoicibaDictYouDict[coarse 词源字典]
coarse: [14] For such an everyday word, the origins of coarse are surprisingly clouded. It first appears in the forms corse or course, and meaning ‘ordinary, everyday’, which has led to speculation that it is an application of the noun course, in the sense ‘the ordinary run of things, the usual practice’; however, not all etymologists accept this. The modern spelling coarse became established in the 18th century.
[coarse etymology, coarse origin, 英语词源]
coarse (adj.)youdaoicibaDictYouDict
early 15c., cors "ordinary" (modern spelling is from late 16c.), probably adjectival use of noun cours (see course (n.)), originally referring to rough cloth for ordinary wear. Developed a sense of "rude" c. 1500 and "obscene" by 1711. Perhaps related, via metathesis, to French gros, which had a similar sense development. Related: Coarsely; coarseness.