IPA: /ˈaʊtˌdɔrz/
KK: /ˈaʊtˌdɔrz/
In or into the open air; outside, away from buildings.
We decided to have a picnic outdoors this weekend.
An area outside, typically in nature, away from buildings and cities.
We love to spend our weekends enjoying activities in the outdoors.
Outdoors is formed from "out" (from Old English "ūtan", meaning outside) and "doors" (from Old English "duru", meaning a barrier or entrance). The word "outdoors" refers to the area outside of buildings, beyond the barriers of doors.
Think of being 'outside' ('out') of 'doors' — that's what outdoors means.