1. To have within itself, to contain, to comprise: Joe's farm includes agricultural land, pastures, and a forest area.

Last evening, Monica and Jerry were dining out with a meal that included an appetizer, the main course, dessert, and coffee.

2. To put in a total, a class, or a group: Ted and his family were buying property for a price that is including the land, a house, and a big two-car garage.

Include can be used in an unrestrictive way implying that there might be other things that are not specifically mentioned or that there is more than what is listed.

3. Etymology: from Latin includere, "to enclose, to shut in"; from in-, "in, into" + claudere, "to shut, to close".