This was thought up while reading the following question:
The dissonant whispers spell has only Verbal components and states:
[...] You whisper a discordant melody that only one creature of your choice within range can hear [...]
The Sage Advice Compendium document states:
Q. Is the sentence of suggestion in the suggestion spell the verbal component, or is the verbal component separate?
A. Verbal components are mystic words (PH, 203), not normal speech. The spell’s suggestion is an intelligible utterance that is separate from the verbal component. The command spell is the simplest example of this principle. The utterance of the verbal component is separate from, and precedes, any verbal utterance that would bring about the spell’s effect.
Is the "discordant melody" the "mystic words" (verbal component) of dissonant whispers? In other words, is the casting of this spell almost unnoticeable outside of the fact that your lips are moving? What is the verbal component of dissonant whispers?