The word "defog" typically means to clear or remove fog from a surface or area. However, there are several antonyms for this word that convey the opposite meaning. These include "fog up," "mist over," and "haze up," all of which indicate an increase in the amount of fog present. Other antonyms for "defog" include "obfuscate," "muddle," and "confuse," all of which suggest a clouding or obscuring of clarity. Overall, these antonyms highlight the importance of clarity and visibility, and remind us that sometimes the opposite of clarity is confusion, rather than simply "more fog.