From Merriam-Webster:

a person who is obstinately or intolerantly devoted to his or her own opinions and prejudices; especially : one who regards or treats the members of a group (such as a racial or ethnic group) with hatred and intolerance

My thought process has never stemmed from an angle of "gay people might not be able to raise children properly." Instead, it was more like, "Will children raised by gay parents have healthy lives? I have no idea." I hadn't actually put any thought into the question; my default answer probably would have been "don't allow those adoptions" simply as a reflexive lean towards the kids' safety.

The point I was attempting to make is that isn't always hatred or intolerance. Sometimes it really is just relatively innocent and well-intentioned ignorance.

Of course, in reality, it's usually hate.