Can I edit auto-complete dictionary?
You can change the words in the user dictionary by going to Settings > Language and Keyboard > User dictionary. From here you can edit as you wish. There is another way mentioned here that may be easier for you: How to remove misspelled words from your Android Dictionary

"Maybe this is more obvious to everyone else, but the dictionary is accessible from the speech-to-text button. The gear icon actually means something! Long-press the microphone to get to the Touch Input settings menu. From there, click User Dictionary and edit out all your "well, crap, I did it again!!!" entries. You can also add entries (at the top), you can long-press an entry to edit, or click the red X to delete."

This is a good article that I have read before. Hope it helps!