Trading and gambling are two different things that one involves luck, the other involves strategy.
In trading, a trader can dream of having a payday through trading as a job, while in gambling you are not sure of having a win in weeks or months. You can't have it as a job, to depend on.
The difference between trading and gambling is clearer, as trading has a long term frame, while for gambling you place a bet, and within a day or two, you are expecting an outcome(short term)