Skimmer comes from skim (from Old French escumer 'to remove scum', from escume 'scum, foam', of Germanic origin) plus the instrumental suffix -er. The historical chain includes Old French escume. Older glosses in the chain include "to remove scum" and "scum, foam", which help explain the semantic range of the modern word. Morphologically, skimmer is best read as suffixal formation and borrowing, yielding an English noun shaped by both form history and later usage. In current English it functions as a noun, with the sense "a utensil or device for removing matter from a liquid surface". related forms include skim, scum, and skimming. The result is an English noun whose etymology preserves the older forms while supporting the word's specialized modern meaning.