Meat that is "juicy" has liquid inside it (in a good way!). The opposite of "juicy" for meat is "dry". "Juicy" can also be used to describe pears, watermelons, berries, tomatoes, hamburgers, etc. The word "juicy" has a positive feeling associated with it. A word with a similar meaning but a negative association is "squishy". If you eat some food that has some kind of liquid inside, but it's not supposed to, you can describe it as "squishy".