The phrase "blue tarp" refers to a large piece of blue colored plastic material that is often used to cover or protect things, like roofs or outdoor items, from rain or other elements. Full definition
She bought a box of canvas bags, a box of blue tarps, several flats of water bottles, and along with the girls, put together «Christmas care packages» for the homeless.Each canvas bag gets filled with a tarp, bottles of water, snacks, food, and a candy cane or two. (redeeminggod.com)
At the end of the talks, Reiss dimmed the lights and amped up the mood with an even grittier sequence shot by the German advocacy group Atlantic Blue: Dolphins were dragged behind a big blue tarp in bundles held together at the tail, like bananas. (discovermagazine.com)
They called us at the Bighorn Basin Project because the site is in our field area, and they'd received reports the bright blue tarp covering the site was sticking out of the ground and could draw attention. (discovermagazine.com)