An electron is a tiny piece of matter with a negative electric charge. In a simple picture of an atom, electrons move around the nucleus in the middle. Electricity in a wire is, at heart, many electrons on the move. The word is basic in school chemistry and physics; you will also hear it in talk about screens, chips, and “electronics,” which grew from this name. Though actually, the name is a blend of electric and ion, and it was coined in 1891 by George Stoney — a little before the particle itself was found in 1896. He had tried other names first, including electrolion and electrine. So the word is older than the tidy textbook story of “they discovered it, then named it.” It is a science word, but a very common one once you leave primary school.