What is the word for the definition of an electron in the highest occupied energy level of an atom

Answer: The word for the definition of an electron in the highest occupied energy level of an atom is " valence electron".

Explanation:

A valence electron is an external shell electron associated with an atom in chemistry and physics that can participate in the creation of a chemical bond if the highest occupied energy level of an atom is not closed. All atoms in a single covalent bond add one valence electron to form a mutual pair.

The periodic table showcases the arrangement of valence electrons group and block wise like:

Alkali metals have n s 1 as external shell configuration like H, Li, Na, K etc. Alkaline metals have n s 2 as external hell configuration like Be, Mg, Ca etc. p-block comprises group 13 to 18 having general electronic configuration n s 2, n p 1-6. d-block or transition metals have general electronic configuration (n-1) d 1-10, n s 1-2. f-block or inner transition metals have general electronic configuration (n-2) f^1-14 (n-1) d^0-1 n s^2.