chemical element

noun
  1. A pure substance consisting of only one type of atom, distinguished by its atomic number, which is the number of protons in its nucleus. Chemical elements are the building blocks of matter and cannot be broken down into simpler substances by chemical means. noun
    Oxygen is a chemical element essential for the respiration of most living organisms.
    Gold is a chemical element that has been highly valued for its rarity and beauty.
  2. A basic substance that cannot be simplified and is a primary constituent of matter, each with unique properties and a specific position in the periodic table. noun
    The periodic table organizes chemical elements based on their atomic number and properties.
    Hydrogen, being the lightest chemical element, is the most abundant in the universe.