Why was clemency trending last week?
1650s, "a begining with the same letter," 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). Formed on model of obliteration, etc. Related: Alliterational.
The repetition of the beginning sounds of words, as in “Peter Piper picked a peck of pickled peppers,” “long-lived,” “short shrift,” and “the fickle finger of fate.”