IPA: /ˈspeɪʃəsnəs/
KK: /ˈspeɪʃəsnəs/
The quality of having a lot of space; being large and open.
The spaciousness of the living room made it feel very comfortable and inviting.
Spaciousness → It is formed from "spacious" (from Latin "spatiosus", meaning having space) and the suffix "-ness" (meaning the state or quality of). The word "spaciousness" refers to the quality of being spacious or having ample space.
Think of 'spacious' meaning having space, and remember that 'spaciousness' describes the quality of being spacious.