可口 (kěkǒu) is a more formal, written way to say 'tasty, delicious' — it describes food or drink that is pleasing to the palate. Unlike the everyday spoken 好吃 (hǎochī), 可口 is often used in product descriptions, menus, or compliments. It focuses on the flavor itself, not on fragrance (香 xiāng) or freshness (鲜 xiān).