The term for the non-reactive element in the periodic table is noble gas. These elements, found in Group 18, are characterized by having a complete valence shell, resulting in minimal chemical reactivity. Examples include helium, neon, and argon, which are inert and do not easily form compounds with other elements. Their unique properties make them useful in various applications, such as lighting and welding. The stability of noble gases is crucial for understanding chemical bonding and the behavior of elements in different conditions.