syntax for env -u foo

[Thufir Hawat]

I want to remove rvm from my env, but cannot seem to.  I see syntax such 
as:

env -u DISPLAY xclock


but it seems like the usual syntax is env -u foo; in any event, my 
particulars:


thufir at caladan:~$ 
thufir at caladan:~$ env | grep rvm
rvm_bin_path=/home/thufir/.rvm/bin
rvm_tar=tar
rvm_path=/home/thufir/.rvm
rvm_uname=Linux
rvm_prefix=/home/thufir
PATH=/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/
usr/bin:/sbin:/bin:/usr/games:/home/thufir/.rvm/bin
rvm_version=1.10.3


I've tried:

env -u rvm
env -u rvm_bin_path

However, maybe I'm not using hte correct syntax?


thufir at caladan:~$ 
thufir at caladan:~$ echo $PATH
/usr/lib/lightdm/lightdm:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/
bin:/sbin:/bin:/usr/games:/home/thufir/.rvm/bin
thufir at caladan:~$ 





thanks,

Thufir