the.com/luncheon

means A formal, often midday meal — lunch dressed up with a proper agenda, like a business meeting, a ceremony, or your grandmother's good china.

from Oddly, 'luncheon' didn't come before 'lunch' — it's the other way around, despite sounding fancier. In the 1600s, 'luncheon' (or 'nuncheon' in earlier forms) meant a hunk or lump of something, especially food — a thick slice of bread or cheese eaten between proper meals. 'Lunch' emerged as a shortening of this older word, and then, confusingly, 'luncheon' stuck around too, eventually drifting upmarket to mean a more formal midday meal while plain 'lunch' stayed casual. So the 'fancier-sounding' word is actually the ancestor, not the descendant.