verb

• (intransitive) To pass lightly; to glide along in an even, smooth course; to glide along near the surface.
  "Not so when swift Camilla scours the plain, / Flies o'er the unbending corn, and skims along the main."
• (transitive) To pass near the surface of; to brush the surface of; to glide swiftly along the surface of.
  "Homer describes Mercury as flinging himself from the top of Olympus, and skimming the surface of the ocean."
• (transitive) To throw an object so it bounces on water.
  "skimming stones"
• (intransitive) To ricochet.

adj

• (of milk) Having lowered fat content.

noun

• (informal) Skim milk.
  "Two percent milk has only a fraction less fat than whole milk, so unless you are feeding a child or someone whose diet requires whole milk, skim is best."