What is the meaning of Potluck?

A meal, especially one offered to a guest, consisting of whatever food is available.

Whatever is available in a particular situation.

A shared meal consisting of whatever guests have brought (sometimes without prior arrangement); a potlatch; also, a dish of food brought to such a meal.

The last draft or portion of an alcoholic beverage in a pot or other drinking vessel.

To take part in a potluck, where each participant brings a meal to be shared by all.

Source: wiktionary.org