The apostrophe serves to show possession or to create a contraction. When the apostrophe is in a contraction, it is replacing one or more letters (e.g., "cannot"->"can't"... the apostrophe replaces the letters "no").
Since an apostrophe isn't those letters, it is an impostor.
Therefore, when the apostrophe is used in a contraction, it is called an "impostorphe."
Them -> 'em (' replaces "th") as in "Let's get 'em!"
The impostorphe is the subsitute or "impostor" for the letters it replaces.
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