Antonyms for "blow skyhigh," which means to completely destroy or ruin something, could include phrases like "build up," "strengthen," "fortify," "protect," or "preserve." Instead of blowing something skyhigh, one could work to make it better, safer, or stronger. Words like "construct," "restore," "reinforce," "rebuild," or "maintain" are all antonyms for the destructive action of blowing something skyhigh. These words imply a more positive approach to problem-solving and a desire to create something lasting and beneficial instead of recklessly destroying it.