One of the most commonly misspelled words these days — particularly in the social media universe — is definite and its related forms.
Folks who mean to tell you that their agreement is definite will instead write that they are defiant. To demonstrate their agreement with the political stance you’ve expressed in your post, they’ll comment “Defiantly!” And since their trust spellchecker won’t tell them otherwise, they’ll assume they’re correct.
Of course, “definite” refers to a level of certitude. If you’re very confident about your belief, stance, or decision, you’ll say “definitely” with pride.
“Defiant,” on the other hand, implies “combative.” Someone who is defiant is disagreeable or argumentative, often for no reason other than to be so. A child with bad manners who refuses to do anything a parent or other adult demands is said to be defiant.
So if you respond to a friend’s comment defiantly, rather than definitely, you may actually be telling them that you angrily disagree with them. Just a cautious reminder that spellcheckers and autocorrect don’t take the place of proofreading.