Flashing

Flashing can refer to indecent exposure (i.e to "flash" one's nude body in public at another unsuspecting person).

Flashing can also mean blinking of a light bulb or computer's cursor.

Flashing also means the weatherproofing shielding put around objects which protrude from the roof of a building (such as pipes and chimneys, or the edges of other roofs) to deflect water away from the seams. Its name likely derives from the fact that metal flashing (typically copper or aluminum) reflects flashes of sunlight. Modern flashing may also be rubber or other waterproof synthetic materials, but metal is still frequently used.