firmaments

Firmaments is the plural of firmament, an old-fashioned or poetic word for the sky or heavens.

The term carries biblical resonance—in Genesis, God creates the firmament to separate the waters above from the waters below.

The word suggests a vast, arching dome: the stars of the firmament, gazing up at the firmament.

Firmaments appears rarely, usually in literary or religious contexts describing multiple celestial expanses or heavenly realms.