firmament
nounUK /ˈfɜːməmənt/
US /ˈfɜːrməmənt/
The sky, especially when you look up and see it as a huge dome over the earth.
The stars sparkled across the firmament on a clear night.
RELATED WORDS
OTHER MEANINGS
2. The arch or vault of heaven in old religious writings.
In the old story, the firmament separated the waters above from the waters below.
3. A strong base or support for something.
The firmament of the bridge was made of solid stone.
4. Any wide, open expanse that seems to stretch overhead.
A firmament of gray clouds hung over the city.