Alliteration is when you use words that have the same sound at the beginning, like "Stellar students synthesize sweet sentences."
It's a time-honored poetic device to make a string of words start with the same consonant sound, and that is what alliteration labels. For example, in A Midsummer's Night Dream, Shakespeare broke out the B's: "With bloody blameful blade he bravely broached his bloody boiling breast." And in the song "From A to G" by Blackalicious, a verse with words beginning with the "C" sound describes a "crazy character, constantly creating concoctions."
