How to revoke a password

I created a user with a password. That newly created user now have
tables and indexes. I want to ALTER that user to exclude the password.
How is this accomplished without dropping and recreating the users?

Larry Bailey
Sr. Oracle DBA
First American Real Estate Solution
(714) 701-3347
lbailey(at)firstam(dot)com
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Thank you. FADLD Tag
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