The re-election of an out-of-office president, for the second time, brings to mind an oddity of the convention of the ordinal numbering of the United States Presidents — those under the Constitution.
George Washington was the first; John Adams the second, and so on the list runs until we get to the curious case of one man, Stephen Grover Cleveland, who is regarded as both the 22nd & 24th presidents. All because the 23rd president, Benjamin Harrison, served between his two presidencies.
Now it is happening to Donald John Trump. He is listed as the 45th president of the United States, having served from 2017 through January of 2021. Now, re-elected after an “interregnum” of the 46th president, Joe Biden, Trump is slated to serve as the 47th president.
It is apparent that, according to this convention, what is being ordered with numbers is the presidencies, not the presidents as such. And it is assumed that a second (or third, or fourth) term in office is the same presidency as the first term of a president, unless broken in sequence by the term of another president.
An odd convention.