英语词源字典 - 在线词源网站

skim (v.)[skim 词源字典]: early 15c. (skimmer, the utensil, is attested from late 14c.), "to clear (a liquid) from matter floating on the surface, lift the scum from," from Old French escumer "remove scum," from escume (Modern French écume) "scum," from a Germanic source (compare Old High German scum "scum," German Schaum; see scum). Meaning "to throw (a stone) so as to skip across the surface of (water) is from 1610s. Meaning "to move lightly and rapidly over the surface of" is from 1650s, from the motion involved in skimming liquid; that of "to glance over carelessly" (in reference to printed matter) recorded by 1799. Related: Skimmed; skimming.[skim etymology, skim origin, 英语词源]
skim-milk (n.): milk from which the cream has been skimmed, 1590s, from skim (v.) + milk (n.).
taffy (n.): coarse candy made from sugar or molasses boiled down and cooled, 1817, related to toffee, but of uncertain origin; perhaps associated with tafia (1763), a rum-like alcoholic liquor distilled from molasses, presumably of West Indian or Malay origin (perhaps a Creole shortening of ratafia). On this theory, the candy would have been made from the syrup skimmed off the liquor during distillation.