(artificial intelligence, computing) A theorem that implies that no single machine learning algorithm is universally the best-performing algorithm for all problems.

Alternative form of there's no such thing as a free lunch

(UK, Canada) Lunch meat.

A container for transporting meals, especially lunch. / (slang) A person or object constantly at one's side (in the manner of a lunchbox). / (British slang) The male genitals when enclosed in clothing.

A formal meal served in the middle of the day. / (obsolete) Any midday meal; lunch. / (obsolete) A lump of food.

(intransitive, dated) To eat luncheon.

The time or hour at or around which lunch is normally eaten. / A break in work or school to eat lunch.

A small diner or restaurant that serves lunch.

A room designated as a place to eat lunch. / A diner or small restaurant that serves lunch.

plural of luncheonette