Blindside is a word that describes being taken by surprise or being caught off guard. Its antonym, therefore, would be a word that describes being aware or prepared. One such antonym is "forewarned" which means to be given advance notice or warning. Another antonym for blindside is "anticipate" which means to expect or predict. Other possible antonyms for blindside include "prepared," "informed," "alert," "ready," and "vigilant." These words all convey a sense of being aware and alert, and more likely to avoid being caught off guard or surprised. By being aware of these antonyms for blindside, we can better prepare ourselves to face unexpected situations.