The debate about this song over on Songmeanings is pretty lively. Kind of silly considering how utterly obvious the song is. I guess if you've never been in a relationship, or tried to be in a relationship with someone and got shot down, then you wouldn't understand, but even then you have to be pretty daft to get this interpretation:

I had originally thought that this word was a negative end to a friendship.. and that the singer was talking about a friendship that no longer had meaning to him. I asked a friend of mine what he meant by four letter word and he said "I end" but that's two words.. and so he alluded it to swears.. however.. on taking a closer look and thinking about it.. to me it reveals itself to be about love (which conveniently happens to be a four-letter word). The "When I go fishing..." stanza tips off that he wants "his friend" to say something besides friend.. and that whenever she calls him a friend.. he just wants to friendship to end so the "love" can begin.. that way the song makes perfect sense to me.. but is almost completely the opposite from what I originally thought.

What the fuck? How can you not know what "a four letter word" means?

I've never really remained friends with any of my exes, although every couple of months I end up hanging out with a certain one a little bit because we get along pretty swell when we're not too busy living our separate lives, but I've certainly never had a relationship end with "let's just be friends".

It's the ultimate snafu, really, saying that, because if you commit any thought to the idea it just seems foolish. You're saying, "I know that by saying this I am implying that it won't hurt you to be around me, after I break your heart right now, and by implying that I am also implying that it won't hurt me to be around you casually, so I must not have any feelings for you any more, which is probably why it doesn't matter to me that it's going to hurt you, but I'm selfish enough to think that not telling you to simply not talk to me anymore will make you feel better because I am so great. Or something, you know, I'm sure it won't kill you to be friends with me."

People are so insensitive!

To be totally honest I've always thought the song was about a girl using a guy for sex and him wishing that it would be more. The four letter word is "f*ck". This song is about a guy in a relationship with a girl that is centered around sex. When she says he's her friend, what he hears is that he's her f*ck, her lay, her saturday savior (a song title which will be posted here sometime), and while they lie in bed together he "goes fishing" for words from her that might expose that she has some sort of feeling for him, but ultimately he knows she'll never love him.

Obviously the lyric "end is the only part of the word, that I heard" screws up this interpretation a bit, but I don't care. I know my interpretation is probably a bit wrong but the mood of the song seems to match this quite well.