Dissonance: Harsh, discordant sounds. Some scholars use the terms dissonance and cacophony synonymously, but others differentiate them, using the latter to refer to harsh or discordant sounds themselves and the former to refer to the use of cacophony to achieve a specific effect.
EXAMPLE: Dissonance in “The Lay of Ike,” the twenty-third of John Berryman’s 77 Dream Songs (1964), signals political opposition to President Dwight D. Eisenhower:
This is the lay of Ike.
Here’s to the glory of the Great White — awk —
who has been running — er — er — things in recent — ech —
in the United — If your screen is black,
ladies & gentlemen, we — I like —
at the Point he was already terrific — sick
to a second term, having done no wrong —
no right — no right — having let the Army — bang —
defend itself from Joe, let venom’ Strauss
bile Oppenheimer out of use — use Robb,
who’ll later fend for Goldfine — Breaking no laws,
he lay in the White House — sob!! — …