Used to denote the means by which a door is bolted (Nehemiah 3:3); a rock in the sea (Jonah 2:6); the shore of the sea (Job 38:10); strong fortifications and powerful impediments, etc. (Isaiah 45:2; Amos 1:5); defences of a city (1 Kings 4:13). A bar for a door was of iron (Isaiah 45:2), brass (Psalm 107:16), or wood (Nahum 3:13).