The New Dictionary of Cultural Literacy, Third Edition. 2002.
elementary particles
The particles that make up the atom. The elementary particles include electrons and a large number of particles, including protons and neutrons, that exist inside the nucleus of atoms. Strictly speaking, the term elementary as applied to most of the particles in the nucleus is inaccurate, for scientists now believe that all the particles except electrons are made of still more elementary particles called quarks.
