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open something out
to unfold or expand something; to open and spread something out. When she opened the fan out, she saw it was made of plastic. The peacock opened out its tail feathers and delighted the children.
1. To become wider: The river opens out as it heads toward the bay.
2. To unfold or expand so that inner parts are displayed; spread out: The couch opened out into a bed.
3. To unfold or expand something; spread something out: I opened the couch out into a bed. Let's open out the model to see how it works.
4. open out on To be a passage or opening to some larger external space: After we remodel, the living room will open out on to the kitchen.