Sea-Legs is the ability to be on a boat and not fall over or vomit.
Sea-Legs can also refer to the short amount of time you're on land after being at sea where it still feels like you're going up and down despite being on land. You will then adjust to the land again.
Sea-Legs also refers to the medication, Meclizine (Bonine). Meclizine helps with nausea and vomiting due to sea sickness and helps with balance. Side effects may include confusion and decreased memory, especially in older people.
Sea-Legs 2 refers to marijuana edibles or smoked or vaped marijuana that is used to prevent nausea and vomiting in boats. In this case, it's used medically. Side effects include being high, munchies, and occasional paranoia.
Stan: I took Sea-Legs (Meclizine)! Now I can keep my balance on the boat and not get nauseous or vomit.