Bible Dictionaries
Firmament

Smith's Bible Dictionary

Firmament. In Scripture, the word denotes an expanse, a wide extent; for such is the signification of the Hebrew word. The original, therefore, does not convey the sense of solidity, but of stretching, extension; the great arch of expanse over our heads, in which are placed the atmosphere and the clouds, and in which the stars appear to be placed, and are really seen. - Webster.

Bibliography Information
Smith, William, Dr. Entry for 'Firmament'. Smith's Bible Dictionary. https://www.studylight.org/​dictionaries/​eng/​sbd/​f/firmament.html. 1901.