Reiteration is the act of saying the same thing again on purpose. You do not repeat it because you forgot. You repeat it so nobody can miss your meaning — in a meeting, a speech, a letter, a classroom. Teachers, bosses, and politicians do this a lot: they come back to the same point, sometimes in slightly different words, to make it land. The word feels formal. In everyday talk people more often say “I’ll say it again,” or they use the verb reiterate (“Let me reiterate…”). The noun turns up in writing and in careful speech. Though actually, doing this can also annoy people, so the word can sound a little stiff, as if you are making a show of being clear. It is not the same as going through a process again and again; that neighbour is iteration, a favourite in computers and design.

重申