Elasticity is skin’s ability to stretch and snap back to its original shape. Loss of skin elasticity is known as elastosis. Elastosis causes skin to look saggy, crinkled, or leathery. Simply put, skin elasticity is your skin’s ability to stretch and then bounce back. Loss of skin elasticity is known officially as elastosis – the degeneration of skin tissue due to ageing and other factors. And solar elastosis occurs to areas of the skin which have too much exposure to the sun and appear more weathered as a result.