This means to use a term more than once in an argument but with a different meaning and context in different uses. For example:
When most people think of virgins, they think of holy and meek people like the Virgin Mary or something. No one would date a man who is still a virgin at twenty.
So there are two uses of the word virgin. The first one relates to a historic virgin with set characteristics of being meek (passive and lacking power). The second use means a twenty year old who hasn’t had sex yet (but not making reference to any personality traits), but there is an assumption in the second sentence based on the way a repeating word was used in the first.
If this comes up when constructing an argument, then always the first step (as I have stated elsewhere) is defining terms.