Definitely vs Defiantly
I used to do this all the time. Thanks to Microsoft Word, my "definetly" was auto-corrected to "defiantly." I see the switch on occasion in query letters and manuscripts, but most often on Facebook from my non-English major friends.
Definition for defiantly:
Use it in a sentence:
Due to Sandra's gangreene, her leg would definitely have to be chopped off.
Sandra screamed defiantly as Tom held her down and I approached her with the sterilized saw.
Hope everyone had a happy and safe Halloween!