alliteration (n.)

1650s, "repetition of the same sound or letter at the beginning of words in close succession," from Modern Latin alliterationem (nominative alliteratio), noun of action from past-participle stem of alliterare "to begin with the same letter," from Latin ad "to" (see ad-) + littera (also litera) "letter, script" (see letter (n.1)). Related: Alliterational.