quark

noun

1. 1.In the Standard Model, an elementary subatomic particle that forms matter. They combine to form hadrons, such as protons and neutrons.
2. 2.(X Window System) An integer that uniquely identifies a text string.
3. 3.A soft creamy cheese, eaten throughout northern, central, and eastern Europe, very similar to cottage cheese except that it is usually not made with rennet.
4. 4.(Falkland Islands) The black-crowned night heron, Nycticorax nycticorax.