Which term describes harsh and dissonant sounds used deliberately in poetry?

The term that refers to harsh and dissonant sounds used deliberately in poetry is cacophony. Cacophony is characterized by a mix of sounds that clash with one another, creating a jarring or unsettling effect. Poets often use cacophony to evoke strong emotions or to emphasize particular moments in their work. This can enhance the imagery or the overall theme, as the unpleasant sounds mirror a sense of conflict, chaos, or intense feeling.

In contrast, euphony refers to pleasing, harmonious sounds that are soothing to the ear, which is quite the opposite of cacophony. Harmony relates more to musical or rhythmic elements rather than sound quality in poetry. Alliteration, on the other hand, is the repetition of initial consonant sounds in a sequence of words, which can contribute to the overall sound of a piece but does not inherently imply dissonance or harshness. Thus, cacophony is the most fitting term to describe the intentional use of harsh and dissonant sounds in poetry.