seal

/siːl/
noun
  1. A marine animal with flippers that lives in cold waters and eats fish.
    • The zoo has a new exhibit where you can watch seals swim and play.
    • A seal popped its head out of the water to look at the boat.
    • Seals often rest on rocks or beaches when they are not hunting.
  2. A device or mark used to close something tightly or to show that something is official or authentic.
    • Check the seal on the milk carton before you buy it.
    • The envelope had a wax seal with the company's logo.
    • The document was stamped with the official seal of the court.
  3. A tight closure that prevents air, water, or other substances from passing through.
    • The rubber seal around the refrigerator door keeps the cold air inside.
    • Make sure the seal on the window is tight to stop drafts.
    • If the seal on the jar is broken, the food might spoil.
verb
  1. To close something tightly so that air, water, or other substances cannot get in or out.
    • Please seal the bag of chips with a clip to keep them fresh.
    • She sealed the letter in an envelope before mailing it.
    • The plumber used tape to seal the leaking pipe.
  2. To make something final or definite.
    • They shook hands to seal the deal on the house sale.
    • Her apology sealed their friendship again.
    • The team's victory sealed their place in the championship game.
  3. To apply a protective coating to a surface.
    • We need to seal the wooden deck before winter to protect it from rain.
    • The artist sealed the painting with a clear varnish.
    • You should seal the grout in the bathroom to prevent mold.
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