Quiet, calm, and not very bright or intense; the opposite of loud or vivid.
From Latin 'subducere' (to lead under or withdraw). The prefix 'sub-' means under, and 'ducere' means to lead. Over time, it evolved to mean conquered or brought under control, then quieted or muted in tone.
Colors in a painting become 'subdued' when artists use grays and muted tones instead of bright primaries—it creates a feeling of sadness or mystery. Photographers actually use this trick all the time to make you feel certain emotions without even realizing it!
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