Definition
An antiquark is the antimatter counterpart to a quark, possessing the same mass but opposite electric charge and other quantum numbers. Quarks are fundamental building blocks of matter, and antiquarks are their 'evil twin' mirror images. While quarks combine to form protons and neutrons, antiquarks can combine with quarks to annihilate each other in a burst of energy. Think of it like +1 and -1 canceling out to zero. Antiquarks are rarely found in everyday matter because of their tendency to annihilate with quarks. They are fleeting particles, existing briefly in high-energy collisions.