unbindall
Removes the bindings from every key at once. It is commonly placed at the top of an autoexec, before any bind lines, so the config starts from a clean state and only the keys you define are active.
unbindall // clear every existing key bind first
bind "f" "use weapon_flashbang" // then declare your own
bind "mouse4" "+voicerecord"
To restore the default keyboard layout instead of clearing everything, use binddefaults.
Examples
unbindall - Without argument it removes every existing key binding. Any input you press afterwards will do nothing until you bind keys again.