The TERM 'Presidential Period' refers to the time period in which a president is in office. This is usually divided into TWO parts: an ERA and a TERM. An ERA is a three-letter word that describes the length of a president's time in office, such as 'ONE' for a single TERM or 'TWO' for TWO terms. A TERM is a four-letter word that describes the length of a president's individual TERM, such as 'four' for a four-year TERM. Together, these TWO words form the phrase 'Presidential Period, ' which is used to refer to the time a president is in office.