In NaOH, the bond between sodium (Na) and oxygen (O) is an ionic bond. In an ionic bond, one or more electrons are transferred completely from one atom to another, creating two oppositely charged ions.

Specifically, in NaOH, sodium loses one electron to oxygen, forming positively charged sodium ions (Na+) and negatively charged oxide ions (O2-). These ions are then strongly attracted to each other due to their opposite charges, resulting in the ionic bond between sodium and oxygen.