
1) Poetic device
Found on
https://www.crosswordclues.com/clue/tautogram

A tautogram (Greek: tauto gramma, `same letter`) is a text in which all words start with the same letter. Historically, tautograms were mostly poetical forms . The difference between a tautogram and alliteration is that tautograms are a written, visual phenomenon, whereas alliterations are a phonetic one. Most cases of alliteration are also taut.....
Found on
http://en.wikipedia.org/wiki/Tautogram
No exact match found.