noun

• (dated) A meal, especially one offered to a guest, consisting of whatever food is available.
  "Here are some leftover beans and meat; we can make a good potluck stew from them."
• (by extension) Whatever is available in a particular situation.
  "He at once resolved to accompany me to that island, ship aboard the same vessel, get into the same watch, the same boat, the same mess with me, in short to share my every hap; with both my hands in his, boldly dip into the Potluck of both worlds."
• (originally Canada, US) 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.
  "Last evening, at the Free Trade Club, a dinner was given by Hon. Robert R. Roosevelt to a large number of his friends. Though invitations had been issued for a week previous, the feast was decidedly of an impromptu character as far the viands went. [...] Cards of invitation of an amusing character were issued, on which the menu was indicated, with the names of the improvised cooks who were to concoct gumbo, lobster cutlets, plumb pudding, various salads, and coffee. [...] Course followed course in the most tumultuous way. Culinary inspirations and cookery nocturnes of all flavors and tastes crowded one on another. Anything like system was discarded, and this was thought likely to destroy the artistic effects of this pot-luck picnic."
• (obsolete) The last draft or portion of an alcoholic beverage in a pot or other drinking vessel.
  "We had but euen pot luck, a little to moyſten our lips, and no more."

verb

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