As a kind of Christmas present, I’m posting this not-quite-a-vocabulary word entry. I know the meaning of all of these words, but there are shades of meaning that I found interesting.
The word repeat means to do something again, or to have something happen again. Note that only one recurrence is enough to be a considered a repeat.
The word iterate, however, implies a larger set. It implies repetition in a bit of an impersonal way. In programming, one can iterate over a set of data, performing the same steps on each item.
The word reiterate implies a sense of repetition with weariness.
The word repeat came into English first, in the mid-1300s; oddly enough, reiterate was next, in the 1400s, followed by iterate in the mid-1500s.
I found the information about interesting, and thus a good candidate for this site.