Can UPDATE statement do something like this...

["Dave Odom" <Dave.Odom@xxxxxxxxxxxx>]

I want to thank Reggie and Elvis for supplying the winning UPDATE SQL syntax to solve my problem.  Here is an example of the SQL:
 
update dodom1/dictionary                                
set S_WORD = substr(S_WORD,1,2)||'O'|| substr(S_WORD,4) 
where S_WORD = 'Rojo'         
 
I was sure there was a way to use SUBSTR for this kind of thing and there is.
 
Thanks again,
 
Dave Odom
Arizona