The highest virtue of those who have no deep convictions. It formerly was the respectful exchange of ideas between two parties in spite of significant disagreement on the topic.
It has now been distorted by liberals to demand agreement with, condoning of and enabling of a point of view regardless of the other party's beliefs and convictions. One demanding this brand of tolerance offers no respect to the other party, does not offer either type of tolerance and often viciously goes on the attack with labels.
You can't say homosexuality is wrong!! That's not showing tolerance! You're just a hateful bigot!