The Enterprise Vault Client for Mac OS X can be un-installed by running the UnInstaller found in the default location:
Library\Application Support\Enterprise Vault\
For version prior to Enterprise Vault 12.x
Library\Application Support\Symantec Enterprise Vault\
Figure 1
Follow the on-screen prompts to uninstall the client. This is the recommended method to uninstall the Enterprise Vault Client for Mac OS X.
Note: A search for UnInstaller should show the result from one of the paths specified above.