tendril

In botany, a slender, threadlike structure that supports a climbing plant by coiling around suitable supports, such as the stems and branches of other plants. It may be a modified stem, leaf, leaflet, flower, leaf stalk, or stipule (a small appendage on either side of the leaf stalk), and may be simple or branched. The tendrils of Virginia creeper Parthenocissus quinquefolia are modified flower heads with suckerlike pads at the end that stick to walls, while those of the grapevine Vitis grow away from the light and thus enter dark crevices where they expand to anchor the plant firmly.