One typo in a description field should be easy with Bulk Edit... One at a time... doing the Item Description only.... 
 
Should take some time... but not as much as when revision one listing at a time....
 
 
 
 
Last year in January my postage information....in each listing... had to be changed
 
I had all of my new information in a separate document  ...  and did a delete/add for over 3000 listings... very easy with Bulk Edit,  one listing at a time....