Luncheon (noun)

1. A light meal typically eaten in the middle of the day, typically between 11am and 2pm.
2. A meal to which people are invited as guests.

Origin:

Mid 16th century: from old french lonchon, from lonchier "provide a lunch", from lonc "long", from latin longus, and -on, from latin -atio(n-). the spelling lunch was in use from the late 17th century, but the variant luncheon remained in use, particularly in formal contexts.

Examples:

1. The luncheon was held in the hotel's grand ballroom.
2. The guests were served sandwiches and tea at the luncheon.
3. The luncheon was a fundraiser for the local charity.
4. The company held a luncheon to celebrate their new partnership.
5. The luncheon was a formal event with a sit-down meal.