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general::
Phrase(s): dim something down
to make lights dim; to use a dimmer to make the lights dimmer. • Why don’t you dim the lights down and put on some music? • Let me dim down the lights and put on some music., Phrase(s): dim down
[for the lights] to go dim. • The lights dimmed down for a few seconds. • Open the stage curtain when the house lights dim down.
McGrawhill's American Idioms And Phrasal Verbs