IPA: /ˈaʊtˌdɔːr/
KK: /ˈaʊtˌdɔr/
Relating to activities or things that take place outside, in the open air.
We love to have outdoor picnics during the summer.
Outdoor → It is formed from "out-" (meaning outside) and "door" (from Old English "duru", meaning a passage or entrance). The word "outdoor" refers to areas or activities that are outside of a building or structure, emphasizing the space beyond the entrance.
Think of being 'outside' ('out-') of a 'door' — that's why outdoor means relating to the area beyond a door.
No commonly confused words.