turn down

verb

1. To refuse, decline, or deny.

   “He turned down all our offers of help.”

   “A local doctor had bought one canvas and but for that lucky chance he would have been out of pocket. Now he was muttering grumpily at Edmund, "Have to get something better this trip, Edmund. Got to pull up somehow or buyers will be turnin' us down. Sales been gettin' worse and worse these last years."”

2. To reduce the power, etc. of something by means of a control, such as the volume, heat, or light.

   “Turn down the television so I can hear myself think.”

   “When it starts to boil, turn down the heat to a simmer.”

3. To reposition by turning, flipping, etc. in a downward direction; to double or fold down.

   “Turn down the blankets to let them air out.”