A light meal usually eaten around midday, notably when not as main meal of the day.
"After skipping dinner last night, I decided to make a hearty sandwich my lunch instead of just grabbing some salad."
In plain English: Lunch is the main meal you eat around midday to get energy for the rest of your day.
"We usually eat lunch at noon in the cafeteria."
Usage: Use "lunch" to refer to the midday meal that typically falls between breakfast and dinner. It is appropriate for any substantial eating occasion at noon, whether it serves as a standalone meal or a lighter option compared to the evening dinner.
To eat lunch.
"I'm going to grab a sandwich and head out for lunch soon."
In plain English: To lunch means to have your midday meal at a restaurant or other place outside your home.
"I will lunch at the new restaurant downtown with my colleagues today."
Usage: Do not use "lunch" as a verb to mean eating; instead, say "have lunch." The word functions only as a noun referring to the midday meal itself.
The word "lunch" originally meant a "piece" or "hunk" when it was first recorded in 1580. Its related form, "luncheon," likely developed through a pattern similar to other words ending in "-ch," though the spelling may have been altered later to seem French.