Adverbial out of doors has 1 sense
- outside, outdoors, out of doors, alfresco - outside a building; "in summer we play outside"
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Noun out of doors has 1 sense
- outdoors, out-of-doors, open air, open - where the air is unconfined; "he wanted to get outdoors a little"; "the concert was held in the open air"; "camping in the open"
--1 is a kind of outside, exterior
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