1. A persistent, abnormal, and irrational fear of a specific thing or situation that compels one to avoid it, despite the awareness and reassurance that it is not dangerous.
2. A strong fear, dislike, or aversion.
In order to silence disagreement or opposition it is not uncommon for people to accuse those who disagree with them of a form of phobia, thus writing them off as abnormal, irrational, fearful when all they are doing is disagreeing. You and I can disagree on something without either of us having a phobia – unless, of course, you suffer with kenophobia, a fear or loathing of me.
For example, when one person has a belief that homosexuality is, for reasons they might give, wrong. A homosexual person might respond that there is nothing wrong with homosexuality. These two people disagree with each other but, because they exercise tolerance, they could get on well with each other as friends, colleagues, neighbours or even relatives. They do not adopt each other’s sexual practices but in every other way their relationship is fine.
However, sometimes one party cannot cope with the disagreement and wants to insist that the other party change their mind. In order to push for this one might accuse the other of homophobia. Or the other might accuse the one of heterophobia. In fact, neither of them might have any fear, dislike or aversion for the other so making these accusations is itself irrational.