test is a virtual command inside bash or what you could call a
/usr/bin/test exists as well as an external
command. Along with builtins and commands there are also
functions which you can think of more like custom builtins. The priority on how they are called are: functions first, builtins second, external binaries or commands last; but you could customize that.
If you have somehow made a function that has the same name as a builtin e.g.
cd, to skip calling the function and call the builtin
cd instead, you could use the builtin command
builtin cd args.
Likewise if you have a builtin that has same name as a command stored in the filesystem e.g.
test, to call the command
test instead, either you give the explicit path e.g.
/usr/bin/test or use the builtin command
command test -n xyz.
To get more idea about it, try running these commands: