A system or state of harsh, discordant, or unpleasant sounds; the opposite of harmony or pleasant sound.
From Greek 'kakos' (bad) + 'phone' (sound, voice); 'cacophonia' is the Latinate form that directly parallels 'symphony' (good sound) in structure.
The word 'cacophony' gets used for ugly sounds, but 'cacophonia' is its more technical form—much like how 'symphony' and 'symphonia' describe music, showing how Latin and Greek gave us pairs of words for the same thing.
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