I first heard the term back when I was going to my local community college and took a Philosophy of Judeo-Christian Principles class. (Sometimes I wonder if I would have ever stopped considering myself a Christian had I never taken that class - but that's another story.) I remember the teacher explaining that he was an agnostic and what that meant. I remember several students, Christians especially, trying to take him to task for this position. I, however, respected it. At the time, I still believed in the basic Christian theology, but I was willing to admit that I didn't "know" that it was true. It was a belief. In other words, I could have been wrong. (And I started to suspect that I was when I learned about pre-Christian religions like Zoroastrianism. Again, another story.)
Flash forward a few years when I was talking to a friend of mine who was a Catholic. I explained that I believed in Jesus and all that, but I had a hard time saying that I "knew" it was true, and I admitted that I had my doubts. However, for the time being, I was going to continue to believe what felt right to me. She said to me, "You sound like an agnostic." While that was a position that I respected, it didn't quite feel right to me. One definition of the word is: "A person who believes that nothing is known or can be known of the existence or nature of God or of anything beyond material phenomena". Considering that I wasn't making any knowledge claims, I acknowledged that it did fit, but still, I was willing to place my bets that a God did exist.
Skip ahead a few more years, and I remember telling my parents that I was an agnostic. I simply did not believe in Christianity. However, I was willing to admit that I could be wrong about that, and I was willing to admit that there might still be a God. I still leaned a bit toward there being one, but I simply wasn't sure.
Several years later, I made an attempt to read The Bible while riding BART to work. I was about halfway through the Old Testament when I decided that there was no way in hell I could believe this stuff. I also remember reasoning that since I no longer believed in the Christian God, and I didn't believe in any other version, then that must have made me an atheist. I figured that "agnostic" didn't quite fit because if somebody pointed a gun to my head and asked me if a God existed, and the wrong answer would result in my brains being splattered everywhere, my gut instinct would be "no".
I still don't think that it's possible to "know" if a god exists, at least when we're talking about it in the deistic sense of the word. Did some intelligent force create the universe for whatever purpose? I don't think so. But how could I "know" it one way or another?
I still go with the term "atheist" because if I look at the word "theism" it's defined as "Belief in the existence of a god or gods, esp. belief in one god as creator of the universe, intervening in it and sustaining a personal relation to his creatures." A theist is a person whose philosophy matches that. Well, mine doesn't. If only there was some handy Greek prefix that I could attach to the word "theist" to indicate that I'm not one of those.
So, skip ahead to the present day. While debating theists, I'm often told that I sound more like an agnostic. Sometimes when debating agnostics, I find out that when we describe our beliefs, we don't seem to disagree on anything other than what we should call ourselves. There was a time when I wanted my self-described agnostic friends to 'fess up that they were atheists too. After all, they claimed no belief in a deity. That technically makes them one. This "agnostic" stance has a "shit or get off the pot" kind of vibe to me. What's wrong with admitting that you don't know something for sure but still having an opinion?
I think I'm finally realizing that it's pointless to argue that though. These are folks who will side with me when it comes to teaching creationism in the classroom and/or basing public policy off of religious tenets. Why make enemies with them?
And maybe when people tell me that I sound more like an agnostic, I should just say: "Sure, why not?"
I don't have to like it though. Maybe I should just stick with the word "skeptic".