Synonyms for Subdued (same or very similar meaning)
WordNet sense 1 (restrained in style or quality):
low-key, low-keyed
WordNet sense 2 (under restraint):
restrained
WordNet sense 3 (in a softened tone):
hushed, muted, quiet
WordNet sense 4 ((of sound) relatively low in volume):
soft
WordNet sense 5 (lacking in light; not bright or harsh):
dim
WordNet sense 6 (devoid of or deficient in light or brightness; shadowed or black):
dark
From the ODE community, based on WordNet
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