"red spots on skin," 1709, perhaps from Fr. rache "a sore," from O.Fr. rache "ringworm," from V.L. *rasicare "to scrape" (cf. O.Prov. rascar, Sp. rascar "to scrape, scratch," It. raschina "itch"), from L. rasus "scraped," pp. of radere "to scrape" (see raze). The connecting
notion is of itching. Sense of "any sudden outbreak or proliferation" first recorded 1820.
rasher
"thin slice of bacon or ham," 1592, of unknown origin. Perhaps from M.E. rash "to cut," var. of rase "to rub, scrape out, erase," from O.Fr. raser (see raze). However, early lexicographer John Minsheu explained it in 1627 as a piece "rashly or hastily roasted."