Strong's #922: bohuw (pronounced bo'-hoo)
from an unused root (meaning to be empty); a vacuity, i.e. (superficially) an undistinguishable ruin:--emptiness, void.
Brown-Driver-Briggs Hebrew Lexicon:
1) emptiness, void, waste
Part of Speech: noun masculine
Relation: from an unused root (meaning to be empty)
This word is used 3 times:
Genesis 1:2: "And the earth was without form, and void; and darkness was upon the face of the deep."
Isaiah 34:11: "it the line of confusion, and the stones of emptiness."
Jeremiah 4:23: "the earth, it was without form, and void; and the heavens, and they had no light."