It also depends on when you're going. Lunch ends earlier during the CP period, but for the rest of the year, it typically transitions at 3 pm. So, a 2:50 pm seating would be considered lunch. Anything after 3 pm would be dinner.
You can look for your specific day of interest on the Disney dining website. When you try to make an ADR, it will show you the meal times on the next page.