What does pcgs 63 pl vam 5 mean on a Morgan silver dollar?

Well, I believe what they mean is that it is the 5th VAM designation of your coin's year (VAM designations are die varieties found in Morgan Dollars, some are worth a lot more than others) and the 63 I believe would refer to the coin's grade as Mint-state 63 (coins are graded on a scale from 1 being barely recognizable to 70 being absolute perfection) and PGS is the grading company that graded the coin.