The act of which two people passionate for each other engage in the physical activity of a Swim followed closely by a Shag. Some may also describe it as a type of water sports. This can also be done concurrently by the skilled, fit or young at heart. Usually taking place by the beach, with total disregard for potential onlookers.
Girl- "it's a perfect time for a swim Jase.
Boy- "it's a great time for a shag babe
boy and girl- ""Let's go for a Swag.