To laminate is to make something, especially paper, stronger and thicker by layering sheets of clear plastic over it. You might want to laminate your flimsy library card to protect it.
Today all states laminate drivers' licenses, making them a sturdy plastic card rather than the insubstantial piece of paper they used to be. You might decide to laminate a poster for a school presentation you're giving, or laminate some old photos to protect them. Most methods used to laminate involve heat and some type of sticky or adhesive substance. The Latin root is lamina, "thin slice, leaf, or layer."