What is the recurrence of words or phrases in a rhetorical device known as?
Repetition, Tricolon or Anaphora
Repetition is three words in a row, such as ‘buy, buy, buy!’.
This could also be a Tricolon, which is just a list of three things, such as ‘he was smart, fast and handsome.’
Finally this could ALSO be Anaphora, which is repetition of a short phrase. Take Abraham Lincolns' Gettysburg Address, ‘government of the people, by the people, for the people’.