Oxymoron: a figure of speech by which a locution produces an incongruous, seemingly self-contradictory effect, as in “cruel kindness” or “to make haste slowly.”
The only word I can think of that you could be mistaking it for is onomatopoeia. When a word sounds like the thing it's describing.
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And no, the way things are said do not make me associate them with anything else. xD