Definition: '.tmux_script.conf' in the Bible refers to a script used by tmux, an integrated terminal emulator for macOS, Linux, and Windows. It's primarily used in bash scripts to set up various configuration options like login screen sizes, window colors, and other visual effects. This is crucial as it allows users to customize their terminal environment specifically for their needs, making it a versatile tool for developers or system administrators looking to tweak the appearance of their terminals.