How can the existing environment variable FOOBAR be suppressed for the execution of the script./myscript only?

`unset -v FOOBAR; ./myscript` would permanently unset `FOOBAR` in the current shell, not just for the `myscript` execution.

`set -a FOOBAR=""; ./myscript` would export `FOOBAR` with an empty string value to the script, not suppress or unset it from the environment.

The `env -u FOOBAR ./myscript` command executes `./myscript` with the `FOOBAR` environment variable specifically unset from its environment, without affecting the `FOOBAR` variable in the calling shell.

`env -i ./myscript` would start `./myscript` with an entirely empty environment (except for any variables explicitly specified with `env`), which is more drastic than just suppressing `FOOBAR`.